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A133649
A007318^(-1) * A133648.
2
1, 4, 9, 19, 37, 75, 149, 299, 597, 1195, 2389, 4779, 9557, 19115, 38229, 76459, 152917, 305835, 611669, 1223339, 2446677, 4893355, 9786709, 19573419, 39146837, 78293675, 156587349, 313174699, 626349397, 1252698795, 2505397589, 5010795179, 10021590357, 20043180715
OFFSET
0,2
FORMULA
Inverse binomial transform of A133648.
From R. J. Mathar, Dec 13 2008: (Start)
a(n) = A062092(n), n > 1.
G.f.: (1+2x)*(1+x+x^2)/((1-2x)*(1+x)). (End)
EXAMPLE
a(3) = (-1, 3, -3, 1) dot (1, 5, 18, 59) = (-1, 15, -54, 59), where A133648 = (1, 5, 18, 59, 184, 561, ...).
MATHEMATICA
CoefficientList[Series[(1 + 2 x) (1 + x + x^2)/((1 - 2 x) (1 + x)), {x, 0, 33}], x] (* Michael De Vlieger, Mar 23 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Sep 19 2007
STATUS
approved