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A139379
A Jacobsthal Catalan convolution.
1
0, 1, 2, 6, 15, 41, 113, 327, 982, 3066, 9892, 32820, 111390, 385042, 1350722, 4795246, 17191535, 62139697, 226167557, 828085651, 3047683955, 11267975677, 41829610607, 155848125601, 582566960465, 2184167358991, 8211247681373
OFFSET
0,3
COMMENTS
Second column of A139377. Row sums of A139377 give a(n+1).
FORMULA
G.f.: xc(x)/(1-x-2x^2), c(x) the g.f. of A000108; a(n)=sum{k=0..n, A000108(k)*A001045(n-k)};
D-finite with recurrence n*a(n) +(6-5*n)*a(n-1) +2*(n-3)*a(n-2) +4*(2*n-3)*a(n-3)=0. - R. J. Mathar, Oct 25 2012
CROSSREFS
Sequence in context: A280788 A121328 A348012 * A236110 A362566 A280782
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Apr 15 2008
STATUS
approved