A192339 Coefficient of x in the reduction of n-th polynomial at A157751 by x^2->x+2.

0, 1, 3, 11, 37, 125, 415, 1371, 4501, 14725, 48031, 156355, 508197, 1649933, 5352255, 17351563, 56226389, 182134837

Offset

1,3

Comments

For an introduction to reductions of polynomials by substitutions such as x^2->x+2, see A192232.

Links

Table of n, a(n) for n=1..18.

Formula

Empirical G.f.: -x^2*(x+1)*(2*x-1)/((x^2+2*x-1)*(4*x^2+2*x-1)). [Colin Barker, Nov 13 2012]

Mathematica

(See A192338.)

Crossrefs

Cf. , A192232, A192313, A192338.

Sequence in context: A134757 A094977 A263986 * A027064 A027066 A291415

Adjacent sequences: A192336 A192337 A192338 * A192340 A192341 A192342

Keyword

nonn

Author

Clark Kimberling, Jun 28 2011

Status

approved