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A134381
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Row sums of triangle A134380.
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2
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1, 2, 5, 15, 52, 205, 921, 4766, 28685, 201159, 1630840, 15071725, 156331161, 1794763970, 22548418541, 307236496071, 4507944378004, 70813851019717, 1185225078743601, 21049903662123422, 395303080572770549, 7825181077750155999, 162835332607069248760
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: (1 + x/((1-x)*S(0) - x))/(1-x), where S(k) = 1 - (k+1)*x/(1 - x - (k+1)*x/S(k+1)); (continued fraction). - Sergei N. Gladkovskii, Feb 05 2015
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EXAMPLE
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a(3) = 15 = (1, 3, 3, 1) dot (1, 1, 2, 5) = (1, + 3 + 6 + 5), where A051295 = 1, 1, 2, 5, 15, 54, 235, ...)
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MATHEMATICA
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max = 20; Clear[g]; g[max + 2] = 1; g[k_] := g[k] = 1 - (k+1)*x/(1 - x - (k+1)*x/g[k+1]; gf = (1 + x/((1-x)*g[0] -x))/(1-x); CoefficientList[Series[gf, {x, 0, max}], x] (* Vaclav Kotesovec, Feb 06 2015, after Sergei N. Gladkovskii *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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