A091950 a(n) = A087659(n) mod 3.

1, 0, 0, 2, 1, 1, 2, 1, 1, 1, 0, 0, 2, 1, 1, 2, 2, 2, 1, 0, 0, 2, 1, 1, 0, 0, 0, 1, 0, 0, 2, 1, 1, 2, 1, 1, 1, 0, 0, 2, 1, 1, 2, 2, 2, 1, 0, 0, 2, 1, 1, 0, 1, 1, 1, 0, 0, 2, 1, 1, 2, 1, 1, 1, 0, 0, 2, 1, 1, 2, 2, 2, 1, 0, 0, 2, 1, 1, 2, 1, 1, 1, 0, 0, 2, 1, 1, 2, 1, 1, 1, 0, 0, 2, 1, 1, 2, 2, 2, 1, 0, 0, 2, 1, 1

Offset

0,4

Links

Table of n, a(n) for n=0..104.

Formula

a(n)=hypergeom([ -n, (n+4)/2, (n+5)/2], [3, 2], -4) mod 3; a(9k)=1, a(9k+1)=0, a(9k+2)=0, a(9k+3)=2, a(9k+4)=1, a(9k+5)=1, a(9k+6)=2*A014578(k+1), a(9k+7)=z(k), a(9k+8)=z(k) where : z(9k)=1, z(9k+1)=2, z(9k+2)=0, z(9k+3)=1, z(9k+4)=2, z(9k+5)=1, z(9k+6)=1, z(9k+7)=2 and z(9k+8)=z(k).

Prog

(PARI) a(n)= sum(i=0, n, 2*binomial(n, i)*(n+2*i+3)!/((i+1)!*(i+2)!*(n+3)!))%3

Crossrefs

Sequence in context: A308424 A317489 A345647 * A014750 A015491 A015776

Adjacent sequences: A091947 A091948 A091949 * A091951 A091952 A091953

Keyword

nonn

Author

Benoit Cloitre, Mar 11 2004

Status

approved