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Orderings of prime signatures

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Prime signatures in graded colexicographic order

In this table, the prime signatures appear in graded colexicographic order, i.e. graded by increasing 
Ω (n)
, i.e. number of prime factors (with repetition), then by colexicographic order of exponents (which nicely sorts by increasing 
ω (n)
, i.e. number of distinct prime factors). With this convention, the prime signature internal order corresponds to the order of exponents of the smallest number with a given prime signature, where the prime factors are commonly listed from smallest to largest.


Prime signatures in graded colexicographic order and their numbers
n
Prime

signature

Sequence A-number Description
1 { } {1} Unit
2 {1} {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, ...} A000040 Prime numbers
3 {2} {4, 9, 25, 49, 121, 169, 289, 361, 529, 841, 961, 1369, 1681, 1849, 2209, 2809, 3481, 3721, ...} A001248 Squares of prime numbers (squarefull biprimes)
4 {1,1} {6, 10, 14, 15, 21, 22, 26, 33, 34, 35, 38, 39, 46, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, ...} A006881 Two distinct prime factors (squarefree biprimes)
5 {3} {8, 27, 125, 343, 1331, 2197, 4913, 6859, 12167, 24389, 29791, 50653, 68921, 79507, ...} A030078 Cubes of prime numbers (cubefull triprimes)
6 {2,1} {12, 18, 20, 28, 44, 45, 50, 52, 63, 68, 75, 76, 92, 98, 99, 116, 117, 124, 147, 148, 153, ...} A054753  
7 {1,1,1} {30, 42, 66, 70, 78, 102, 105, 110, 114, 130, 138, 154, 165, 170, 174, 182, 186, 190, 195, ...} A007304 Three distinct prime factors (sphenic numbers) (squarefree triprimes)
8 {4} {16, 81, 625, 2401, 14641, 28561, 83521, 130321, 279841, 707281, 923521, 1874161, ...} A030514 Fourth powers of prime numbers (biquadratefull tetraprimes)
9 {3,1} {24, 40, 54, 56, 88, 104, 135, 136, 152, 184, 189, 232, 248, 250, 296, 297, 328, 344, 351, ...} A065036  
10 {2,2} {36, 100, 196, 225, 441, 484, 676, 1089, 1156, 1225, 1444, 1521, 2116, 2601, 3025, 3249, ...} A085986 Squares of squarefree biprimes
11 {2,1,1} {60, 84, 90, 126, 132, 140, 150, 156, 198, 204, 220, 228, 234, 260, 276, 294, 306, 308, 315, ...} A085987  
12 {1,1,1,1} {210, 330, 390, 462, 510, 546, 570, 690, 714, 770, 798, 858, 870, 910, 930, 966, 1110, 1122, ...} A046386 Four distinct prime factors (squarefree tetraprimes)
13 {5} {32, 243, 3125, 16807, 161051, 371293, 1419857, 2476099, 6436343, 20511149, 28629151, ...} A050997 Fifth powers of primes (powerfull pentaprimes)
14 {4,1} {48, 80, 112, 162, 176, 208, 272, 304, 368, 405, 464, 496, 567, 592, 656, 688, 752, 848, ...} A178739  
15 {3,2} {72, 108, 200, 392, 500, 675, 968, 1125, 1323, 1352, 1372, 2312, 2888, 3087, 3267, 4232, ...} A143610 (subset of Achilles numbers)
16 {3,1,1} {120, 168, 180, 252, 264, 270, 280, 300, 312, 378, 396, 408, 440, 450, 456, 468, 520, ...} A179642  
17 {2,2,1} {180, 252, 300, 396, 450, 468, 588, 612, 684, 700, 828, 882, 980, 1044, 1100, 1116, 1300, ...} A179643  
18 {2,1,1,1} {420, 630, 1050, 1470, ...} A??????  
19 {1,1,1,1,1} {2310, 2730, 3570, 3990, 4290, 4830, 5610, 6006, 6090, 6270, 6510, 6630, 7410, 7590, ...} A046387 Five distinct prime factors (squarefree pentaprimes)
20 {6} {64, 729, 15625, 117649, 1771561, 4826809, 24137569, 47045881, 148035889, 594823321, ...} A030516 Sixth powers of primes (powerfull hexaprimes)
21 {5,1} {96, 160, 224, 352, 416, 486, 544, 608, 736, 928, 992, 1184, 1215, 1312, 1376, 1504, 1696, ...} A178740  
22 {4,2} {144, 324, 400, 784, 1936, 2025, 2500, 2704, 3969, 4624, 5625, 5776, 8464, 9604, 9801, ...} NOT QUITE A030633

15 divisors

{4,2} and {14}

(subset of square numbers)
23 {3,3} {216, 1000, 2744, 3375, 9261, 10648, 17576, 35937, 39304, 42875, 54872, 59319, 97336, ...} A162142 Cubes of squarefree biprimes
24 {4,1,1} {240, 336, 528, 560, 624, 810, 816, 880, 912, 1040, 1104, 1134, 1232, 1360, 1392, 1456, ...} A179644  
25 {3,2,1} {360, 504, 540, 600, 756, 792, 936, 1176, 1188, 1224, 1350, 1368, 1400, 1404, 1500, 1656, ...} A163569  
26 {2,2,2} {900, 1764, 4356, 4900, 6084, 10404, 11025, 12100, 12996, 16900, 19044, 23716, 27225, ...} A162143 Squares of squarefree triprimes
27 {3,1,1,1} {840, 1320, 1560, 1848, 1890, 2040, 2184, 2280, 2760, 2856, 2970, 3080, 3192, 3432, 3480, ...} A179670  
28 {2,2,1,1} {1260, 1980, 2100, 2340, 2772, 2940, 3060, 3150, 3276, 3300, 3420, 3900, 4140, 4284, ...} A179690  
29 {2,1,1,1,1} {4620, 6930, ...} A??????  
30 {1,1,1,1,1,1} {30030, 39270, 43890, 46410, 51870, 53130, 62790, 66990, 67830, 71610, 72930, 79170, ...} A067885 Six distinct prime factors (squarefree hexaprimes)
31 {7} {128, 2187, 78125, 823543, 19487171, 62748517, 410338673, 893871739, 3404825447, ...} A092759 Seventh powers of primes (powerfull heptaprimes)
32 {6,1} {192, 320, 448, 704, 832, 1088, 1216, 1458, 1472, 1856, 1984, 2368, 2624, 2752, 3008, ...} NOT QUITE A030632

14 divisors

{6,1} and {13}

 
33 {5,2} {288, 800, 972, 1568, 3872, 5408, 6075, 9248, 11552, 11907, 12500, 16928, 26912, 28125, ...} A179646 (subset of Achilles numbers)
34 {4,3} {432, 648, 2000, 5000, 5488, 10125, 16875, 19208, 21296, 27783, 35152, 64827, 78608, ...} A179666 (subset of Achilles numbers)
35 {5,1,1} {480, 672, 1056, 1120, 1248, 1632, 1760, 1824, 2080, 2208, 2430, 2464, 2720, 2784, 2912, ...} A179667  
36 {4,2,1} {720, 1008, 1200, 1584, 1620, 1872, 2268, 2352, 2448, 2736, 2800, 3312, 3564, 3920, 4050, ...} A179669  
37 {3,3,1} {1080, 1512, 2376, 2808, 3000, 3672, 4104, 4968, 6264, 6696, 6750, 7000, 7992, 8232, ...} A179688  
38 {3,2,2} {1800, 2700, 3528, 4500, 5292, 8712, 9800, 12168, 12348, 13068, 18252, 20808, 24200, ...} A179695 (subset of Achilles numbers)
39 {4,1,1,1} {1680, 2640, 3120, 3696, 4080, 4368, 4560, 5520, 5670, 5712, 6160, 6384, 6864, 6960, ...} A179693  
40 {3,2,1,1} {2520, 3780, 3960, 4200, 4680, 5544, 5880, 5940, 6120, 6552, 6600, 6840, 7020, 7800, ...} A179700  
41 {2,2,2,1} {6300, 22050, ...} A??????  
42 {3,1,1,1,1} {9240, ...} A??????  
43 {2,2,1,1,1} {13860, ...} A??????  
44 {2,1,1,1,1,1} {60060, 450450, ...} A??????  
45 {1,1,1,1,1,1,1} {510510, 4849845, 37182145, 215656441, 955049953, 3212440751, 10131543907, ...} A046325 Seven distinct prime factors (squarefree heptaprimes)
46 {8} {256, 6561, 390625, 5764801, 214358881, 815730721, 6975757441, 16983563041, ...} A179645 Eighth powers of primes (powerfull octaprimes)
47 {7,1} {384, 640, 896, 1408, 1664, 2176, 2432, 2944, 3712, 3968, 4374, 4736, 5248, 5504, 6016, ...} A179664  
48 {6,2} {576, 1600, 2916, 3136, 7744, 10816, 18225, 18496, 23104, 33856, 35721, 53824, 61504, ...} NOT QUITE A137484

21 divisors

{6,2} and {20}

(subset of square numbers)
49 {5,3} {864, 1944, 4000, 10976, 25000, 30375, 42592, 70304, 83349, 84375, 134456, 157216, ...} A179671 (subset of Achilles numbers)
50 {4,4} {1296, 10000, 38416, 50625, 194481, 234256, 456976, 1185921, 1336336, 1500625, ...} NOT QUITE A137488

25 divisors

{4,4} and {24}

Biquadrates of squarefree biprimes
51 {6,1,1} {960, 1344, 2112, 2240, 2496, 3264, 3520, 3648, 4160, 4416, 4928, 5440, 5568, 5824, 5952, ...} A179672  
52 {5,2,1} {1440, 2016, 2400, 3168, 3744, 4704, 4860, 4896, 5472, 5600, 6624, 6804, 7840, 8352, ...} A179691  
53 {4,3,1} {2160, 3024, 3240, 4536, 4752, 5616, 6000, 7128, 7344, 8208, 8424, 9936, 11016, 12312, ...} A179698  
54 {4,2,2} {3600, 8100, ...} A?????? (subset of square numbers)
55 {3,3,2} {5400, 13500, ...} A?????? (subset of Achilles numbers)
56 {5,1,1,1} {3360, 17010, ...} A??????  
57 {4,2,1,1} {5040, 11340, ...} A??????  
58 {3,3,1,1} {7560, ...} A??????  
59 {3,2,2,1} {12600, ...} A??????  
60 {2,2,2,2} {44100, ...} A?????? Squares of squarefree tetraprimes
61 {4,1,1,1,1} {18480, ...} A??????  
62 {3,2,1,1,1} {27720, ...} A??????  
63 {2,2,2,1,1} {69300, ...} A??????  
64 {3,1,1,1,1,1} {120120, ...} A??????  
65 {2,2,1,1,1,1} {180180, ...} A??????  
66 {2,1,1,1,1,1,1} {1021020, ...} A??????  
67 {1,1,1,1,1,1,1,1} {9699690, 11741730, 13123110, 14804790, 15825810, 16546530, 17160990, 17687670, ...} A123322 Eight distinct prime factors (squarefree octaprimes)

Prime signatures in the order of increasing smallest numbers of prime signatures

In this table, the prime signatures appear in the order of increasing smallest numbers of prime signatures. Note that the prime signatures are not graded by increasing 
Ω (n)
. The exponents are listed in decreasing order. With this convention, the prime signature internal order corresponds to the order of exponents of the smallest numbers of prime signatures, where the prime factors are commonly listed from smallest to largest.


Prime signatures in the order of increasing smallest numbers of prime signatures and their numbers
n
Prime

signature

Sequence A-number Description
1 { } {1} Unit
2 {1} {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, ...} A000040 Prime numbers
3 {2} {4, 9, 25, 49, 121, 169, 289, 361, 529, 841, 961, 1369, 1681, 1849, 2209, 2809, 3481, 3721, ...} A001248 Squares of prime numbers (squarefull biprimes)
4 {1,1} {6, 10, 14, 15, 21, 22, 26, 33, 34, 35, 38, 39, 46, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, ...} A006881 Two distinct prime factors (squarefree biprimes)
5 {3} {8, 27, 125, 343, 1331, 2197, 4913, 6859, 12167, 24389, 29791, 50653, 68921, 79507, ...} A030078 Cubes of prime numbers (cubefull triprimes)
6 {2,1} {12, 18, 20, 28, 44, 45, 50, 52, 63, 68, 75, 76, 92, 98, 99, 116, 117, 124, 147, 148, 153, ...} A054753  
7 {4} {16, 81, 625, 2401, 14641, 28561, 83521, 130321, 279841, 707281, 923521, 1874161, ...} A030514 Fourth powers of prime numbers (biquadratefull tetraprimes)
8 {3,1} {24, 40, 54, 56, 88, 104, 135, 136, 152, 184, 189, 232, 248, 250, 296, 297, 328, 344, 351, ...} A065036  
9 {1,1,1} {30, 42, 66, 70, 78, 102, 105, 110, 114, 130, 138, 154, 165, 170, 174, 182, 186, 190, 195, ...} A007304 Three distinct prime factors (sphenic numbers) (squarefree triprimes)
10 {5} {32, 243, 3125, 16807, 161051, 371293, 1419857, 2476099, 6436343, 20511149, 28629151, ...} A050997 Fifth powers of primes (powerfull pentaprimes)
11 {2,2} {36, 100, 196, 225, 441, 484, 676, 1089, 1156, 1225, 1444, 1521, 2116, 2601, 3025, 3249, ...} A085986 Squares of squarefree biprimes
12 {4,1} {48, 80, 112, 162, 176, 208, 272, 304, 368, 405, 464, 496, 567, 592, 656, 688, 752, 848, ...} A178739  
13 {2,1,1} {60, 84, 90, 126, 132, 140, 150, 156, 198, 204, 220, 228, 234, 260, 276, 294, 306, 308, 315, ...} A085987  
14 {6} {64, 729, 15625, 117649, 1771561, 4826809, 24137569, 47045881, 148035889, 594823321, ...} A030516 Sixth powers of primes (powerfull hexaprimes)
15 {3,2} {72, 108, 200, 392, 500, 675, 968, 1125, 1323, 1352, 1372, 2312, 2888, 3087, 3267, 4232, ...} A143610 (subset of Achilles numbers)
16 {5,1} {96, 160, 224, 352, 416, 486, 544, 608, 736, 928, 992, 1184, 1215, 1312, 1376, 1504, 1696, ...} A178740  
17 {3,1,1} {120, 168, 180, 252, 264, 270, 280, 300, 312, 378, 396, 408, 440, 450, 456, 468, 520, ...} A179642  
18 {7} {128, 2187, 78125, 823543, 19487171, 62748517, 410338673, 893871739, 3404825447, ...} A092759 Seventh powers of primes (powerfull heptaprimes)
19 {4,2} {144, 324, 400, 784, 1936, 2025, 2500, 2704, 3969, 4624, 5625, 5776, 8464, 9604, 9801, ...} NOT QUITE A030633

15 divisors

{4,2} and {14}

(subset of square numbers)
20 {2,2,1} {180, 252, 300, 396, 450, 468, 588, 612, 684, 700, 828, 882, 980, 1044, 1100, 1116, 1300, ...} A179643  
21 {6,1} {192, 320, 448, 704, 832, 1088, 1216, 1458, 1472, 1856, 1984, 2368, 2624, 2752, 3008, 3392, ...} NOT QUITE A030632

14 divisors

{6,1} and {13}

 
22 {1,1,1,1} {210, 330, 390, 462, 510, 546, 570, 690, 714, 770, 798, 858, 870, 910, 930, 966, 1110, 1122, ...} A046386 Four distinct prime factors (squarefree tetraprimes)
23 {3,3} {216, 1000, 2744, 3375, 9261, 10648, 17576, 35937, 39304, 42875, 54872, 59319, 97336, ...} A162142 Cubes of squarefree biprimes
24 {4,1,1} {240, 336, 528, 560, 624, 810, 816, 880, 912, 1040, 1104, 1134, 1232, 1360, 1392, 1456, ...} A179644  
25 {8} {256, 6561, 390625, 5764801, 214358881, 815730721, 6975757441, 16983563041, ...} A179645 Eighth powers of primes (powerfull octaprimes)
26 {5,2} {288, 800, 972, 1568, 3872, 5408, 6075, 9248, 11552, 11907, 12500, 16928, 26912, 28125, ...} A179646 (subset of Achilles numbers)
27 {3,2,1} {360, 504, 540, 600, 756, 792, 936, 1176, 1188, 1224, 1350, 1368, 1400, 1404, 1500, 1656, ...} A163569  
28 {7,1} {384, 640, 896, 1408, 1664, 2176, 2432, 2944, 3712, 3968, 4374, 4736, 5248, 5504, 6016, ...} A179664  
29 {2,1,1,1} {420, 630, 1050, 1470, ...} A??????  
30 {4,3} {432, 648, 2000, 5000, 5488, 10125, 16875, 19208, 21296, 27783, 35152, 64827, 78608, ...} A179666 (subset of Achilles numbers)
31 {5,1,1} {480, 672, 1056, 1120, 1248, 1632, 1760, 1824, 2080, 2208, 2430, 2464, 2720, 2784, 2912, ...} A179667  
32 {9} {512, 19683, 1953125, 40353607, 2357947691, 10604499373, 118587876497, 322687697779, ...} A179665 Ninth powers of primes (powerfull nonaprimes)
33 {6,2} {576, 1600, 2916, 3136, 7744, 10816, 18225, 18496, 23104, 33856, 35721, 53824, 61504, ...} NOT QUITE A137484

21 divisors

{6,2} and {20}

(subset of square numbers)
34 {4,2,1} {720, 1008, 1200, 1584, 1620, 1872, 2268, 2352, 2448, 2736, 2800, 3312, 3564, 3920, 4050, ...} A179669  
35 {8,1} {768, 13122, 781250, 1171875, ...} A??????  
36 {3,1,1,1} {840, 1320, 1560, 1848, 1890, 2040, 2184, 2280, 2760, 2856, 2970, 3080, 3192, 3432, 3480, ...} A179670  
37 {5,3} {864, 1944, 4000, 10976, 25000, 30375, 42592, 70304, 83349, 84375, 134456, 157216, ...} A179671 (subset of Achilles numbers)
38 {2,2,2} {900, 1764, 4356, 4900, 6084, 10404, 11025, 12100, 12996, 16900, 19044, 23716, 27225, ...} A162143 Squares of squarefree triprimes
39 {6,1,1} {960, 1344, 2112, 2240, 2496, 3264, 3520, 3648, 4160, 4416, 4928, 5440, 5568, 5824, 5952, ...} A179672  
40 {10} {1024, 59049, 9765625, 282475249, 25937424601, 137858491849, 2015993900449, ...} A030629 Tenth powers of primes (powerfull decaprimes)
41 {3,3,1} {1080, 1512, 2376, 2808, 3000, 3672, 4104, 4968, 6264, 6696, 6750, 7000, 7992, 8232, ...} A179688  
42 {7,2} {1152, 8748, 312500, 703125, ...} A?????? (subset of Achilles numbers)
43 {2,2,1,1} {1260, 1980, 2100, 2340, 2772, 2940, 3060, 3150, 3276, 3300, 3420, 3900, 4140, 4284, ...} A179690  
44 {4,4} {1296, 10000, 38416, 50625, 194481, 234256, 456976, 1185921, 1336336, 1500625, ...} NOT QUITE A137488

25 divisors

{4,4} and {24}

Biquadrates of squarefree biprimes
45 {5,2,1} {1440, 2016, 2400, 3168, 3744, 4704, 4860, 4896, 5472, 5600, 6624, 6804, 7840, 8352, ...} A179691  
46 {9,1} {1536, 39366, 3906250, 5859375, ...} A??????  
47 {4,1,1,1} {1680, 2640, 3120, 3696, 4080, 4368, 4560, 5520, 5670, 5712, 6160, 6384, 6864, 6960, ...} A179693  
48 {6,3} {1728, ...} A?????? (subset of cube numbers)
49 {3,2,2} {1800, 2700, 3528, 4500, 5292, 8712, 9800, 12168, 12348, 13068, 18252, 20808, 24200, ...} A179695 (subset of Achilles numbers)
50 {7,1,1} {1920, ...} A??????  
51 {11} {2048, 177147, 48828125, 1977326743, 285311670611, 1792160394037, 34271896307633, ...} A079395 Eleventh powers of primes (powerfull hendecaprimes)
52 {4,3,1} {2160, 3024, 3240, 4536, 4752, 5616, 6000, 7128, 7344, 8208, 8424, 9936, 11016, 12312, ...} A179698  
53 {8,2} {2304, 26244, ...} A?????? (subset of square numbers)
54 {1,1,1,1,1} {2310, 2730, 3570, 3990, 4290, 4830, 5610, 6006, 6090, 6270, 6510, 6630, 7410, 7590, 7770, ...} A046387 Five distinct prime factors (squarefree pentaprimes)
55 {3,2,1,1} {2520, 3780, 3960, 4200, 4680, 5544, 5880, 5940, 6120, 6552, 6600, 6840, 7020, 7800, 8280, ...} A179700  
56 {5,4} {2592, ...} A?????? (subset of Achilles numbers)
57 {6,2,1} {2880, ...} A??????  
58 {10,1} {3072, 118098, 19531250, 29296875, ...} A??????  
59 {5,1,1,1} {3360, 17010, ...} A??????  
60 {7,3} {3456, ...} A?????? (subset of Achilles numbers)
61 {4,2,2} {3600, 8100, ...} A?????? (subset of square numbers)
62 {8,1,1} {3840, ...} A??????  
63 {12} {4096, 531441, 244140625, 13841287201, 3138428376721, 23298085122481, ...} A030631 Twelfth powers of primes (powerfull dodecaprimes)
64 {5,3,1} {4320, ...} A??????  
65 {9,2} {4608, 78732, ...} A?????? (subset of Achilles numbers)
66 {2,1,1,1,1} {4620, 6930, ...} A??????  
67 {4,2,1,1} {5040, 11340, ...} A??????  
68 {6,4} {5184, ...} A?????? (subset of square numbers)
69 {3,3,2} {5400, 13500, ...} A?????? (subset of Achilles numbers)
70 {7,2,1} {5760, ...} A??????  
71 {11,1} {6144, 354294, ...} A??????  
72 {2,2,2,1} {6300, 22050, ...} A??????  
73 {4,4,1} {6480, ...} A??????  
74 {6,1,1,1} {6720, ...} A??????  
75 {8,3} {6912, ...} A?????? (subset of Achilles numbers)
76 {5,2,2} {7200, ...} A?????? (subset of Achilles numbers)
77 {3,3,1,1} {7560, ...} A??????  
78 {9,1,1} {7680, ...} A??????  
79 {5,5} {7776, 100000, 759375, ...} A?????? Fifth powers of squarefree biprimes
80 {13} {8192, 1594323, 1220703125, 96889010407, 34522712143931, 302875106592253, ...} A138031 Thirteenth powers of primes (powerfull tridecaprimes)
81 {6,3,1} {8640, ...} A??????  
82 {10,2} {9216, ...} A?????? (subset of square numbers)
83 {3,1,1,1,1} {9240, ...} A??????  
84 {5,2,1,1} {10080, ...} A??????  
85 {7,4} {10368, ...} A?????? (subset of Achilles numbers)
86 {4,3,2} {10800, ...} A?????? (subset of Achilles numbers)
87 {8,2,1} {11520, ...} A??????  
88 {12,1} {12288, 1062882, ...} A??????  
89 {3,2,2,1} {12600, ...} A??????  
90 {5,4,1} {12960, ...} A??????  
91 {7,1,1,1} {13440, ...} A??????  
92 {9,3} {13824, ...} A?????? (subset of cube numbers)
93 {2,2,1,1,1} {13860, ...} A??????  
94 {6,2,2} {14400, ...} A?????? (subset of square numbers)
95 {4,3,1,1} {15120, ...} A??????  
96 {10,1,1} {15360, ...} A??????  
97 {6,5} {15552, ...} A?????? (subset of Achilles numbers)
98 {14} {16384, 4782969, 6103515625, ...} A?????? Fourteenth powers of primes (powerfull tetradecaprimes)

Sequences

A118914 Concatenation of the prime signatures (in increasing order of exponents of prime power components) of the positive integers.

{1, 1, 2, 1, 1, 1, 1, 3, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 4, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 3, 2, 1, 1, 3, 1, 2, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 4, 2, 1, 2, ...}

A036035 Least integer of each prime signature, in graded (colexicographic order or reflected colexicographic order) of exponents.

{1, 2, 4, 6, 8, 12, 30, 16, 24, 36, 60, 210, 32, 48, 72, 120, 180, 420, 2310, 64, 96, 144, 216, 240, 360, 900, 840, 1260, 4620, 30030, 128, 192, 288, 432, 480, 720, 1080, 1800, 1680, 2520, 6300, 9240, ...}
A046523 Smallest number with same prime signature as 
n
.
{1, 2, 2, 4, 2, 6, 2, 8, 4, 6, 2, 12, 2, 6, 6, 16, 2, 12, 2, 12, 6, 6, 2, 24, 4, 6, 8, 12, 2, 30, 2, 32, 6, 6, 6, 36, 2, 6, 6, 24, 2, 30, 2, 12, 12, 6, 2, 48, 4, 12, 6, 12, 2, 24, 6, 24, 6, 6, 2, 60, 2, 6, 12, 64, 6, 30, 2, ...}

A025487 Least integer of each prime signature; also products of primorial numbers A002110.

{1, 2, 4, 6, 8, 12, 16, 24, 30, 32, 36, 48, 60, 64, 72, 96, 120, 128, 144, 180, 192, 210, 216, 240, 256, 288, 360, 384, 420, 432, 480, 512, 576, 720, 768, 840, 864, 900, 960, 1024, 1080, 1152, 1260, 1296, ...}

A181087 Prime signatures in the order of increasing smallest numbers of prime signatures.

{1, 2, 1, 1, 3, 1, 2, 4, 1, 3, 1, 1, 1, 5, 2, 2, 1, 4, 1, 1, 2, 6, 2, 3, 1, 5, 1, 1, 3, 7, 2, 4, 1, 2, 2, 1, 6, 1, 1, 1, 1, 3, 3, 1, 1, 4, 8, 2, 5, 1, 2, 3, 1, 7, 1, 1, 1, 2, 3, 4, 1, 1, 5, 9, 2, 6, 1, 2, 4, 1, 8, 1, 1, 1, 3, 3, 5, ...}

A095904 Triangular array of natural numbers (greater than 1) arranged by prime signature.

{2, 3, 4, 5, 9, 6, 7, 25, 10, 8, 11, 49, 14, 27, 12, 13, 121, 15, 125, 18, 16, 17, 169, 21, 343, 20, 81, 24, 19, 289, 22, 1331, 28, 625, 40, 30, 23, 361, 26, 2197, 44, 2401, 54, 42, 32, 29, 529, 33, 4913, 45, ...}

Sequences related to ordered prime signatures

The ordered prime signatures (where the order of exponents matters) correspond to compositions of 
Ω (n)
instead of partitions of 
Ω (n)
.

A055932 Least integer of each ordered prime signatures.

{1, 2, 4, 6, 8, 12, 16, 18, 24, 30, 32, 36, 48, 54, 60, 64, 72, 90, 96, 108, 120, 128, 144, 150, 162, 180, 192, 210, 216, 240, 256, 270, 288, 300, 324, 360, 384, 420, 432, 450, 480, 486, 512, 540, 576, ...}

A096903 Least integer of each ordered prime signatures (A055932) arranged by prime signature (each row starting with least integer of each prime signature, A025487).

{1, 2, 4, 6, 8, 12, 18, 16, 24, 54, 30, 32, 36, 48, 162, 60, 90, 150, 64, 72, 108, 96, 486, 120, 270, 750, 128, 144, 324, 180, 300, 450, 192, 1458, 210, 216, 240, 810, 3750, 256, 288, 972, 360, 540, 600, ...}

See also


  • A179665
    p 9
    with 
    p
    prime.
  • A179668 Products of the 
    8
    th power of a prime and a distinct prime 
    (p 8q)
    .
  • A179689 Products of 
    2
    distinct primes 
    (p 7q 2)
    .
  • A179696 Products of 
    3
    distinct primes 
    (p 7q r)
    .
  • A179694 Products of 
    2
    distinct primes 
    (p 6q 3)
    .


  • A030629 Numbers with 
    11
    divisors. (Prime(n)^10.)
  • A179692 Products of 
    2
    distinct primes 
    (p 9q)
    .
  • A179699 Products of 
    2
    distinct primes 
    (p 8q 2)
    .
  • A179696 Numbers with prime signature 
    {7, 1, 1}
    , i.e. of form 
    p 7qr
    with 
    p, q
    and 
    r
    prime.



External links