A267896 a(n) = (Prime(n+1)^2 - Prime(n)^2) / 8.

2, 3, 9, 6, 15, 9, 21, 39, 15, 51, 39, 21, 45, 75, 84, 30, 96, 69, 36, 114, 81, 129, 186, 99, 51, 105, 54, 111, 420, 129, 201, 69, 360, 75, 231, 240, 165, 255, 264, 90, 465, 96, 195, 99, 615, 651, 225, 114, 231, 354, 120, 615, 381, 390, 399, 135, 411, 279

Offset: 2

Author

Franklin T. Adams-Watters, Jan 22 2016

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 2..10000

Crossrefs

Cf. A069482, A028334, A024675, A000040.

Programs

Magma

[(NthPrime(n+1)^2-NthPrime(n)^2) div 8: n in [2..60]]; // Vincenzo Librandi, Jan 23 2016

Maple

seq((ithprime(n+1)^2 - ithprime(n)^2)/8, n=2..100); # Robert Israel, Jan 22 2016

Mathematica

Rest[Array[(Prime[# + 1]^2 - Prime[#]^2) / 8 &, 60]] (* Vincenzo Librandi, Jan 23 2016 *)
(#[[2]]-#[[1]])/8&/@Partition[Prime[Range[2,60]]^2,2,1] (* Harvey P. Dale, Aug 01 2022 *)

PARI

a(n) = (prime(n+1)^2 - prime(n)^2)/8; \\ Michel Marcus, Jan 22 2016

Formula

a(n) = A024675(n) * A028334(n) / 2.

a(n) = (A000040(n+1)^2 - A000040(n)^2) / 8.

a(n) = A069482(n) / 8.