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 A006155 Expansion of 1/(2-x-e^x). (Formerly M1945) 2
 1, 2, 9, 61, 551, 6221, 84285, 1332255, 24066691, 489100297, 11044268633, 274327080611, 7433424980943, 218208342366093, 6898241919264181, 233651576126946103, 8441657595745501019, 324052733365292875025 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 REFERENCES Getu, S.; Shapiro, L. W.; Combinatorial view of the composition of functions. Ars Combin. 10 (1980), 131-145. N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 157 FORMULA E.g.f.: 1/(2-x-exp(x)). a(n) ~ n! / ((1+c) * (2-c)^(n+1)), where c = A226571 = LambertW(exp(2)). - Vaclav Kotesovec, Jun 06 2019 MATHEMATICA With[{nn=20}, CoefficientList[Series[1/(2-x-E^x), {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Apr 27 2018 *) CROSSREFS Cf. A032112. Sequence in context: A192939 A107883 A088182 * A121870 A268450 A146887 Adjacent sequences:  A006152 A006153 A006154 * A006156 A006157 A006158 KEYWORD nonn,easy AUTHOR EXTENSIONS More terms from Ralf Stephan, Mar 12 2004 STATUS approved

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Last modified October 21 22:47 EDT 2019. Contains 328315 sequences. (Running on oeis4.)