A106189 Expansion of 1/((1-2x^2)sqrt(1-4x)).

1, 2, 8, 24, 86, 300, 1096, 4032, 15062, 56684, 214880, 818800, 3133916, 12038200, 46384432, 179193920, 693849254, 2691994060, 10462833808, 40729251920, 158772196436, 619716378280, 2421643356592, 9472863484160, 37090890396284

Offset

0,2

Comments

Diagonal sums of A112336. - Paul Barry, Sep 04 2005

Links

Table of n, a(n) for n=0..24.

Formula

a(n)=sum{k=0..floor(n/2), binomial(2(n-2k), n-2k)*2^k}.

Mathematica

CoefficientList[Series[1/((1-2x^2)Sqrt[1-4x]), {x, 0, 30}], x] (* Harvey P. Dale, Dec 21 2025 *)

Crossrefs

Sequence in context: A094038 A007223 A385239 * A106183 A357160 A362139

Adjacent sequences: A106186 A106187 A106188 * A106190 A106191 A106192

Keyword

easy,nonn

Author

Paul Barry, Apr 24 2005

Status

approved