%I A002999
%S A002999 1,2,6,18,56,170,492,1358,3600,9234,23060,56342,135192,
%T A002999 319514,745500,1720350,3932192,8912930,20054052,44826662,
%U A002999 99614760,220201002,484442156,1061158958,2315255856,5033164850
%N A002999 Expansion of (1+x*exp(x))^2.
%F A002999 a(0) = 1, a(n) = (n^2-n)2^n/4 + 2n. a(n) = A003013(n) + n = A001815(n) 
               + 2n. - Ralf Stephan (ralf(AT)ark.in-berlin.de), Sep 02 2003
%Y A002999 Cf. A048482, A001787, A005183.
%Y A002999 Sequence in context: A066158 A148456 A148457 this_sequence A091142 A111961 
               A071721
%Y A002999 Adjacent sequences: A002996 A002997 A002998 this_sequence A003000 A003001 
               A003002
%K A002999 nonn
%O A002999 0,2
%A A002999 N. J. A. Sloane (njas(AT)research.att.com).