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A293470
a(n) = [x^n] (1/(1 - x/(1 - 2*x/(1 - 3*x/(1 - 4*x/(1 - 5*x/(1 - 6*x/(1 - ...))))))))^n, a continued fraction.
1
1, 1, 7, 64, 691, 8506, 117586, 1811902, 30977059, 585159526, 12157511122, 276365651992, 6835179127294, 182885413524568, 5265255383238592, 162296482607602714, 5332203008816278819, 185989603728568482598, 6863252473075010369626, 267102762222709967674384, 10932746393513621360731066
OFFSET
0,3
FORMULA
a(n) ~ 2^(n + 1/2) * n^(n+1) / exp(n - 1/2). - Vaclav Kotesovec, Sep 16 2021
MATHEMATICA
Table[SeriesCoefficient[1/(1 + ContinuedFractionK[-k x, 1, {k, 1, n}])^n, {x, 0, n}], {n, 0, 20}]
Table[SeriesCoefficient[Sum[(2 k - 1)!! x^k, {k, 0, n}]^n, {x, 0, n}], {n, 0, 20}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Oct 09 2017
STATUS
approved