A087917 Number of unordered ways to write n as a sum of 3 odious numbers (A000069).

0, 0, 1, 1, 1, 2, 1, 1, 2, 3, 2, 3, 3, 2, 4, 6, 5, 5, 6, 5, 6, 8, 8, 9, 9, 8, 10, 12, 12, 14, 14, 10, 14, 19, 14, 18, 20, 14, 19, 25, 21, 20, 27, 22, 23, 32, 26, 27, 31, 29, 31, 36, 35, 35, 39, 34, 38, 47, 40, 42, 47, 40, 43, 60, 53, 44, 60, 50, 48, 68, 62, 54, 64, 65, 58, 75

Offset

1,6

Links

Table of n, a(n) for n=1..76.

Formula

a(n) = sum(i+j+k=n, A010060(i)*A010060(j)*A010060(k)) - Benoit Cloitre, Mar 19 2004

Prog

(PARI) a(n)=sum(i=1, n, sum(j=1, i, sum(k=1, j, if(i+j+k-n, 0, A010060(i)*A010060(j)*A010060(k)))))

Crossrefs

Cf. A087916.

Cf. A010060.

Sequence in context: A091093 A049615 A114919 * A330334 A087741 A054991

Adjacent sequences: A087914 A087915 A087916 * A087918 A087919 A087920

Keyword

nonn,easy

Author

Ralf Stephan, Oct 18 2003

Status

approved