

A099493


Expansion of (1+x^2)^2/(1+x^22x^3+x^4+x^6).


1



1, 0, 1, 2, 1, 0, 3, 4, 3, 8, 7, 10, 23, 8, 33, 56, 1, 104, 121, 58, 297, 232, 291, 780, 349, 1072, 1903, 174, 3407, 4272, 1505, 9840, 8543, 8752, 26321, 13902, 33777, 65456, 11805, 110356, 150173, 35192, 325303, 310054, 257319, 885496, 537919, 1054888, 2240927
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OFFSET

0,4


COMMENTS

A Chebyshev transform of A052907, which has g.f. 1/(12x^22x^3). The image of G(x) under the Chebyshev transform is (1/(1+x^2))G(x/(1+x^2)).


LINKS

Table of n, a(n) for n=0..48.


FORMULA

a(n)=a(n2)+2a(n3)a(n4)a(n6); a(n)=sum{k=0..floor(n/2), C(nk, k)(1)^k*sum{j=0.., floor(n2k/2), C(j, n2k2j)2^j}}.


CROSSREFS

Sequence in context: A221542 A221463 A135488 * A088523 A222211 A145460
Adjacent sequences: A099490 A099491 A099492 * A099494 A099495 A099496


KEYWORD

easy,sign


AUTHOR

Paul Barry, Oct 19 2004


STATUS

approved



