OFFSET
1,5
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1000
FORMULA
G.f.: Product_{k>=1} (1 + x^A005384(k)). - Andrew Howroyd, Dec 28 2017
EXAMPLE
e(16) = #{11+5, 11+3+2} = 2.
PROG
(PARI)
ok(n)={isprime(n) && isprime(2*n+1)}
{my(n=80); Vec(prod(k=1, n, 1 + if(ok(k), x^k + O(x*x^n), 0))-1, -n)} \\ Andrew Howroyd, Dec 28 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Aug 09 2009
STATUS
approved