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A032115 "BIJ" (reversible, indistinct, labeled) transform of 1,3,5,7... 1
1, 1, 4, 17, 120, 1169, 13980, 195649, 3130288, 56345057, 1126900980, 24791821361, 595003712424, 15470096522737, 433162702636300, 12994881079088609, 415836194530835040, 14138430614048390849, 508983502105742069988, 19341373080018198658897 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..200

C. G. Bower, Transforms (2)

FORMULA

E.g.f.: (1 + 2*(1-2*x)*exp(x) - (1-2*x)^2*exp(2*x))/(2*(1-2*x)*exp(x)). - Andrew Howroyd, Sep 12 2018

a(n) ~ n! * 2^(n-1) * exp(-1/2). - Vaclav Kotesovec, Sep 13 2018

PROG

(PARI) seq(n)={my(p=1 + (2*x-1)*exp(x + O(x*x^n))); Vec(serlaplace((1-p^2/2)/(1-p)))} \\ Andrew Howroyd, Sep 12 2018

CROSSREFS

Sequence in context: A240323 A206353 A260694 * A054927 A071138 A032325

Adjacent sequences:  A032112 A032113 A032114 * A032116 A032117 A032118

KEYWORD

nonn

AUTHOR

Christian G. Bower

EXTENSIONS

a(0)=1 prepended and terms a(18) and beyond from Andrew Howroyd, Sep 12 2018

STATUS

approved

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Last modified November 17 04:27 EST 2018. Contains 317275 sequences. (Running on oeis4.)