A030006 a(n) = (prime(n)-1)*(prime(n)-5)/12.

0, 1, 5, 8, 16, 21, 33, 56, 65, 96, 120, 133, 161, 208, 261, 280, 341, 385, 408, 481, 533, 616, 736, 800, 833, 901, 936, 1008, 1281, 1365, 1496, 1541, 1776, 1825, 1976, 2133, 2241, 2408, 2581, 2640, 2945, 3008, 3136, 3201, 3605, 4033, 4181, 4256, 4408, 4641

Offset

3,3

Comments

Confirmed a(n) = A242090(n) for 3 <= n <= 4000. - Fausto A. C. Cariboni, Feb 23 2019

Links

T. D. Noe, Table of n, a(n) for n = 3..1000

Mathematica

Table[(p - 1) (p - 5)/12, {p, Prime[Range[3, 50]]}] (* T. D. Noe, Apr 16 2012 *)
((#-1)(#-5))/12&/@Prime[Range[3, 60]] (* Harvey P. Dale, Aug 13 2023 *)

Crossrefs

Cf. A000040.

Sequence in context: A365316 A001082 A242090 * A229849 A357276 A088586

Adjacent sequences: A030003 A030004 A030005 * A030007 A030008 A030009

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved