OFFSET
1,5
LINKS
PROG
(PARI) a(n)=my(s); forprime(p=2^n+1, 2^(n+1), s+=valuation(p+1, 2)%2==0); s \\ Charles R Greathouse IV, Oct 09 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 04 2004
STATUS
approved