A166926 A000004 preceded by 1, 2, 4.

1, 2, 4, 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 A058331.

Links

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

Formula

a(0) = 1, a(1) = 2, a(2) = 4, a(n) = 0 for n > 2.

G.f.: (1+2*x+4*x^2).

a(n) = 2^n mod 8. - Ridouane Oudra, Apr 08 2025

Prog

(PARI) {concat([1, 2, 4], vector(102))}

Crossrefs

Cf. A000004 (zero sequence), A058331 (2*n^2+1), A130706 (1, 2, 0, 0, 0, 0, ...), A130779 (1, 1, 2, 0, 0, 0, 0, ...).

Sequence in context: A082871 A321406 A383856 * A266296 A028573 A138758

Adjacent sequences: A166923 A166924 A166925 * A166927 A166928 A166929

Keyword

easy,nonn

Author

Klaus Brockhaus, Oct 23 2009

Status

approved