a(n) = n! * [x^n] W(-x)*(W(-x) + 2)/(W(-x) + 1), where W denotes Lambert's W function.

A061302

a(n) = n! * [x^n] W(-x)*(W(-x) + 2)/(W(-x) + 1), where W denotes Lambert's W function.

Terms

    a(0) =0a(1) =2a(2) =6a(3) =36a(4) =320a(5) =3750a(6) =54432a(7) =941192a(8) =18874368a(9) =430467210a(10) =11000000000a(11) =311249095212

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