A169585 A000004 preceded by 1, 3.

1, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

Offset

0,2

Comments

Inverse binomial transform of A016777; second inverse binomial transform of A053220; third inverse binomial transform of A027471 without first term; fourth inverse binomial transform of A081039.

Links

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

Formula

a(0) = 1, a(1) = 3, a(n) = 0 for n > 1.

G.f.: 1+3*x.

a(n) = 3^n mod 9. - Ridouane Oudra, Apr 09 2025

Prog

(PARI) {concat([1, 3], vector(103))}

Crossrefs

Cf. A000004 (zero sequence), A016777 (3*n+1), A053220 ((3*n-1)*2^(n-2)), A027471 ((n-1)*3^(n-2)), A081039 ((3*n+4)*4^(n-1), a(0)=1, a(1)=7), A130706 (1, 2, 0, 0, 0, ...), A166926 (1, 2, 4, 0, 0, 0, ...), A130779 (1, 1, 2, 0, 0, 0, ...).

Sequence in context: A186718 A319625 A307802 * A045840 A181000 A335453

Adjacent sequences: A169582 A169583 A169584 * A169586 A169587 A169588

Keyword

easy,nonn

Author

Klaus Brockhaus, Dec 02 2009

Status

approved