OFFSET
1,4
COMMENTS
Partial sums of number of subsets of {1,2,...,n} such that every number in the set is no larger than the sum of the other numbers in the set. See formula in A095944. The subsequence of primes begins: 5, 53, 757, 2090009, 16762853.
EXAMPLE
a(9) = 0 + 0 + 1 + 4 + 13 + 35 + 85 + 194 + 425 = 757 is prime.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Jonathan Vos Post, Dec 25 2010
STATUS
approved