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A293120
Expansion of e.g.f. exp(x^2/(1+x)).
3
1, 0, 2, -6, 36, -240, 1920, -17640, 183120, -2116800, 26943840, -374220000, 5628934080, -91122071040, 1579034096640, -29155689763200, 571308920582400, -11838533804697600, 258608278645516800, -5938673374272038400, 143003892952893772800
OFFSET
0,3
LINKS
FORMULA
E.g.f.: exp(x^2/(1+x)).
a(n) = (-1)^n * A052845(n).
a(n) ~ (-1)^n * n^(n-1/4) * exp(-3/2 + 2*sqrt(n) - n)/sqrt(2). - Vaclav Kotesovec, Sep 30 2017
MATHEMATICA
CoefficientList[Series[E^(x^2/(1+x)), {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Sep 30 2017 *)
PROG
(PARI) x='x+O('x^66); Vec(serlaplace(exp(x^2/(1+x))))
CROSSREFS
Column k=1 of A293133.
Cf. A052845.
Sequence in context: A375796 A375799 A002869 * A052845 A052832 A058583
KEYWORD
sign
AUTHOR
Seiichi Manyama, Sep 30 2017
STATUS
approved