

A117374


Expansion of (13x)/(1x^2+x^3).


2



1, 3, 1, 4, 4, 5, 8, 9, 13, 17, 22, 30, 39, 52, 69, 91, 121, 160, 212, 281, 372, 493, 653, 865, 1146, 1518, 2011, 2664, 3529, 4675, 6193, 8204, 10868, 14397, 19072, 25265, 33469
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OFFSET

0,2


COMMENTS

Diagonal sums of number triangle A117372.


LINKS

Table of n, a(n) for n=0..36.
Index entries for linear recurrences with constant coefficients, signature (0,1,1).


FORMULA

a(n)=a(n2)+a(n3); a(n)=sum{k=0..floor(n/2), (1)^n*(C(k,n2k)+3*C(k, n2k1))}.


CROSSREFS

Sequence in context: A260502 A014388 A186693 * A202142 A021322 A277129
Adjacent sequences: A117371 A117372 A117373 * A117375 A117376 A117377


KEYWORD

easy,sign


AUTHOR

Paul Barry, Mar 10 2006


STATUS

approved



