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Cubes that are a sum of the cubes of three primes.
2

%I #32 May 25 2017 22:06:54

%S 128787625,153130375,356400829,647214625,1102302937,1115157653,

%T 1214767763,1454419637,3463512697,14796346375,18630700451,21184951663,

%U 21323063917,21740999671,24820429213,29704593673,32005984375,38580208939,51770001583,53540005609,68769820673,74352915125,89374579111,94507253875,113872553423

%N Cubes that are a sum of the cubes of three primes.

%C See comment in A258865.

%H Chai Wah Wu, <a href="/A258262/b258262.txt">Table of n, a(n) for n = 1..367</a>

%e . n | a(n)

%e . ----+----------------------------------------------------

%e . 1 | 128787625 | 505^3 | 59^3 + 163^3 + 499^3

%e . 2 | 153130375 | 535^3 | 349^3 + 379^3 + 383^3

%e . 3 | 356400829 | 709^3 | 193^3 + 461^3 + 631^3

%e . 4 | 647214625 | 865^3 | 11^3 + 607^3 + 751^3

%e . 5 | 1102302937 | 1033^3 | 599^3 + 691^3 + 823^3

%e . 6 | 1115157653 | 1037^3 | 59^3 + 233^3 + 1033^3

%e . 7 | 1214767763 | 1067^3 | 97^3 + 269^3 + 1061^3

%e . 8 | 1454419637 | 1133^3 | 577^3 + 797^3 + 911^3

%e . 9 | 3463512697 | 1513^3 | 337^3 + 967^3 + 1361^3

%e . 10 | 14796346375 | 2455^3 | 1049^3 + 1789^3 + 1993^3

%e . 11 | 18630700451 | 2651^3 | 281^3 + 1889^3 + 2281^3

%e . 12 | 21184951663 | 2767^3 | 103^3 + 2179^3 + 2213^3

%e . 13 | 21323063917 | 2773^3 | 331^3 + 467^3 + 2767^3

%e . 14 | 21740999671 | 2791^3 | 769^3 + 1879^3 + 2447^3

%e . 15 | 24820429213 | 2917^3 | 31^3 + 1951^3 + 2591^3

%e . 16 | 29704593673 | 3097^3 | 1237^3 + 2081^3 + 2659^3

%e . 17 | 32005984375 | 3175^3 | 809^3 + 1789^3 + 2953^3

%e . 18 | 38580208939 | 3379^3 | 641^3 + 1993^3 + 3121^3

%e . 19 | 51770001583 | 3727^3 | 1399^3 + 1667^3 + 3541^3

%e . 20 | 53540005609 | 3769^3 | 11^3 + 1783^3 + 3631^3

%e . 21 | 68769820673 | 4097^3 | 1187^3 + 1861^3 + 3929^3

%e . 22 | 74352915125 | 4205^3 | 1657^3 + 1697^3 + 4019^3

%e . 23 | 89374579111 | 4471^3 | 1931^3 + 3163^3 + 3697^3

%e . 24 | 94507253875 | 4555^3 | 521^3 + 2833^3 + 4153^3

%e . 25 | 113872553423 | 4847^3 | 593^3 + 1237^3 + 4817^3 .

%o (Haskell)

%o a258262 n = a258262_list !! (n-1)

%o a258262_list = filter ((== 1) . a010057) a258865_list

%Y Cf. A010057, A258865, A030078, A048766.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Jun 13 2015