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A046926
Number of ways to express n as p+2q; p, q primes.
3
0, 0, 0, 0, 0, 1, 1, 1, 2, 0, 2, 1, 2, 0, 2, 1, 4, 0, 2, 0, 3, 0, 3, 1, 3, 0, 4, 1, 4, 0, 2, 0, 5, 0, 3, 1, 4, 0, 4, 1, 5, 0, 4, 0, 6, 0, 4, 1, 4, 0, 7, 0, 5, 0, 3, 0, 7, 0, 3, 1, 3, 0, 7, 1, 7, 0, 5, 0, 7, 0, 4, 0, 4, 0, 8, 1, 7, 0, 5, 0, 8, 0, 4, 1, 7, 0, 8, 1, 7, 0, 4, 0, 11, 0, 5, 1, 6, 0, 9
OFFSET
1,9
PROG
(PARI) a(n)=my(s); forprime(p=2, n\2-1, if(isprime(n-2*p), s++)); s \\ Charles R Greathouse IV, Jul 22 2015
CROSSREFS
Sequence in context: A353698 A341345 A068067 * A200815 A074398 A144765
KEYWORD
nonn
STATUS
approved