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%I #13 Oct 01 2017 00:18:24
%S 1,0,-2,6,-12,0,240,-2520,21840,-181440,1481760,-11642400,80498880,
%T -311351040,-4739454720,183437654400,-4300276780800,88851284121600,
%U -1754954007206400,34107089784768000,-659574028252339200,12724865943229440000,-244046146272658329600
%N E.g.f.: exp(-x^2/(1+x)).
%H Seiichi Manyama, <a href="/A293122/b293122.txt">Table of n, a(n) for n = 0..450</a>
%F a(n) = (-1)^n * A293117(n).
%t CoefficientList[Series[E^(-x^2/(1+x)), {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Sep 30 2017 *)
%o (PARI) x='x+O('x^66); Vec(serlaplace(exp(-x^2/(1+x))))
%Y Column k=1 of A293134.
%Y Cf. A293117.
%K sign
%O 0,3
%A _Seiichi Manyama_, Sep 30 2017