A167891 A000004 preceded by 1, 4, 2.

1, 4, 2, 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

Author

Klaus Brockhaus, Nov 14 2009

Keywords

• easy
• nonn

Comments

Inverse binomial transform of A028387.

Crossrefs

Cf. A000004 (zero sequence), A028387 (n+(n+1)^2), A166926 (1, 2, 4, 0, 0, 0, 0, ...), A130706 (1, 2, 0, 0, 0, 0, ...), A130779 (1, 1, 2, 0, 0, 0, 0, ...), A167858 (3, 14, 36, 36, 12, 0, 0, 0, ...), A167876 (1, 3, 4, 2, 0, 0, 0, ...).

Programs

PARI

{concat([1, 4, 2], vector(100))}

Formula

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

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