A119332 - OEIS

A119332

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

1, 1, 0, 0, 2, 2, 0, 0, 4, 4, 0, 0, 8, 8, 0, 0, 16, 16, 0, 0, 32, 32, 0, 0, 64, 64, 0, 0, 128, 128, 0, 0, 256, 256, 0, 0, 512, 512, 0, 0, 1024, 1024, 0, 0, 2048, 2048, 0, 0, 4096, 4096, 0, 0, 8192, 8192, 0, 0, 16384, 16384, 0, 0, 32768

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OFFSET

0,5

COMMENTS

Row sums of A119331. Binomial transform is A119330.

LINKS

Table of n, a(n) for n=0..60.

Index entries for linear recurrences with constant coefficients, signature (0,0,0,2).

FORMULA

a(n)=sum{k=0..n, sum{i=0..n, (-1)^(n-i)*C(n,i)*sum{j=0..i-k, C(k,2j)*C(i-k,2j)*2^j}}}.

MATHEMATICA

CoefficientList[Series[(1+x)/(1-2x^4), {x, 0, 90}], x] (* or *) LinearRecurrence[{0, 0, 0, 2}, {1, 1, 0, 0}, 90] (* Harvey P. Dale, Jul 21 2024 *)

CROSSREFS

Sequence in context: A301400 A134315 A268584 * A335683 A089262 A376943

Adjacent sequences: A119329 A119330 A119331 * A119333 A119334 A119335

KEYWORD

easy,nonn

AUTHOR

Paul Barry, May 14 2006

STATUS

approved