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A135177
a(n) = p^2*(p-1), where p = prime(n).
5
4, 18, 100, 294, 1210, 2028, 4624, 6498, 11638, 23548, 28830, 49284, 67240, 77658, 101614, 146068, 201898, 223260, 296274, 352870, 383688, 486798, 564898, 697048, 903264, 1020100, 1082118, 1213594, 1283148, 1430128, 2032254, 2230930
OFFSET
1,1
FORMULA
a(n) = p^3 - p^2 = A030078(n) - A001248(n).
a(n) = A000010(prime(n)^3). - R. J. Mathar, Oct 15 2017
Sum_{n>=1} 1/a(n) = A152441. - Amiram Eldar, Nov 09 2020
From Amiram Eldar, Nov 22 2022: (Start)
Product_{n>=1} (1 + 1/a(n)) = A065483.
Product_{n>=1} (1 - 1/a(n)) = A065414. (End)
EXAMPLE
a(4) = 294 because the 4th prime number is 7, 7^2 = 49, 7-1 = 6 and 49 * 6 = 294.
MATHEMATICA
Table[Prime[n]^3-Prime[n]^2, {n, 1, 12}] (* Vladimir Joseph Stephan Orlovsky, Apr 29 2008 *)
Table[p^3-p^2, {p, Prime[Range[40]]}] (* Harvey P. Dale, Jan 15 2015 *)
PROG
(Magma)[(p^3-p^2): p in PrimesUpTo(200)]; // Vincenzo Librandi, Dec 15 2010
(PARI) forprime(p=2, 1e3, print1(p^2*(p-1)", ")) \\ Charles R Greathouse IV, Jun 16 2011
CROSSREFS
Cf. A001248 (p^2), A030078 (p^3), A045991 (n^2 * (n-1)), A065414, A065483, A152441.
Sequence in context: A263688 A197593 A084832 * A244309 A137958 A371543
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Nov 25 2007
STATUS
approved