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Expansion of e.g.f. 1/(1 - x*exp(x) + x^2*exp(2*x)).
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%I #15 Mar 17 2020 07:25:09

%S 1,1,2,-3,-92,-1015,-8274,-35483,496280,18127377,344895130,4427896781,

%T 15653147412,-1300426685831,-53961316375498,-1345994948213355,

%U -20836853905979984,60576513730122017,19579099820703961266,894668319876527296669,26059066415716831363820

%N Expansion of e.g.f. 1/(1 - x*exp(x) + x^2*exp(2*x)).

%H Jinyuan Wang, <a href="/A002983/b002983.txt">Table of n, a(n) for n = 0..300</a>

%t nmax=20; CoefficientList[Series[1/(1-x*Exp[x]+x^2*Exp[2*x]), {x, 0, nmax}], x] Range[0, nmax]! (* _Jinyuan Wang_, Mar 17 2020 *)

%o (PARI) my(x='x+O('x^25)); Vec(serlaplace(1/(1 - x*exp(x) + x^2*exp(2*x)))) \\ _Michel Marcus_, Mar 17 2020

%K sign

%O 0,3

%A _N. J. A. Sloane_

%E More terms from _Jinyuan Wang_, Mar 17 2020