A358638 Number of partitions of n into at most 2 distinct nonprime parts.

1, 1, 0, 0, 1, 1, 1, 1, 1, 2, 3, 1, 2, 2, 3, 3, 4, 2, 4, 3, 4, 4, 6, 3, 6, 5, 7, 5, 7, 5, 8, 6, 7, 7, 10, 7, 11, 7, 9, 9, 11, 8, 12, 9, 11, 10, 13, 9, 14, 11, 14, 11, 14, 11, 16, 13, 15, 13, 17, 13, 19, 14, 16, 15, 19, 15, 21, 15, 17, 17, 21, 16, 22, 17, 21, 18, 22, 18, 25, 18, 22

Offset

0,10

Links

Table of n, a(n) for n=0..80.

Formula

For n > 0, a(n) = A005171(n) + A302479(n).

Prog

(PARI) A358638(n) = if(n<2, 1, !isprime(n)+sum(k=1, (n-1)\2, !(isprime(k)+isprime(n-k)))); \\ Antti Karttunen, Nov 25 2022

Crossrefs

Cf. A005171, A018252, A096258, A302479, A347788, A358639, A358640.

Sequence in context: A121884 A079087 A324920 * A236855 A244232 A227781

Adjacent sequences: A358635 A358636 A358637 * A358639 A358640 A358641

Keyword

nonn

Author

Ilya Gutkovskiy, Nov 24 2022

Status

approved