A328999 Dirichlet g.f. = Product_{primes p == 1 (mod 12)} (1+p^(-s))^2/(1-p^(-s))^2) * Product_{primes p == +-5 (mod 12)} (1+p^(-2*s))/(1-p^(-2*s).

1, 4, 2, 4, 2, 4, 4, 0, 4, 4, 0, 0, 0, 4, 8, 4, 4, 0, 0, 4, 4, 0, 0, 4, 2, 0, 4, 8, 4, 4, 2, 4, 0, 4, 4, 4, 4, 0, 4, 0, 16, 0, 0, 0, 0, 4, 0, 0, 4, 0, 4, 4, 2, 8, 0, 4, 4, 0, 0, 4, 0, 4, 0, 4, 4, 0, 16, 0, 0, 4, 2, 4, 0, 4, 0, 0, 0, 8, 4, 16, 2, 0, 0, 4, 4, 4

Offset

0,2

Links

Table of n, a(n) for n=0..85.

Michael Baake and Peter A. B. Pleasants, Algebraic solution of the coincidence problem in two and three dimensions, Zeitschrift für Naturforschung A 50.8 (1995): 711-717. See page 714.

Example

The D.g.f. is 1 + 4/13^s + 2/25^s + 4/37^s + ... .

Prog

(PARI) a(n) = direuler(p = 2, 12*n-11, (1 + (p%12==1)*X)^2/(1 - (p%12==1)*X)^2 * (1 + ((p%12==5)+(p%12==7))*X^2)/(1 - ((p%12==5)+(p%12==7))*X^2))[12*n-11]; \\ Amiram Eldar, May 11 2024

Crossrefs

Sequence in context: A209272 A105397 A373422 * A236185 A300004 A147973

Adjacent sequences: A328996 A328997 A328998 * A329000 A329001 A329002

Keyword

nonn

Author

N. J. A. Sloane, Nov 14 2019

Extensions

More terms from Amiram Eldar, May 11 2024

Status

approved