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 A032346 Essentially shifts 1 place right under inverse binomial transform. 5
 1, 1, 2, 6, 21, 82, 354, 1671, 8536, 46814, 273907, 1700828, 11158746, 77057021, 558234902, 4230337018, 33448622893, 275322101318, 2354401779494, 20878592918183, 191682453823420, 1819147694792802, 17822073621801123 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS With leading 0 and offset 1, number of permutations beginning with 21 and avoiding 3-12. - Ralf Stephan, Apr 25 2004 LINKS N. J. A. Sloane, Transforms Sergey Kitaev, Generalized pattern avoidance with additional restrictions, Sem. Lothar. Combinat. 48 (2003), Article B48e. Sergey Kitaev, Partially Ordered Generalized Patterns, Discrete Math. 298(1-3) (2005), 212-229. Sergey Kitaev and Toufik Mansour, Simultaneous avoidance of generalized patterns, arXiv:math/0205182 [math.CO], 2002. FORMULA With offset 1, e.g.f.: x + exp(exp(x)) * int[0..x, exp(-exp(t))*sum(n>=1, t^n/n!) dt]. - Ralf Stephan, Apr 25 2004 MATHEMATICA max = 23; f[x_] = x + Exp[Exp[x]]*Integrate[Exp[-Exp[t]]*Sum[t^n/n!, {n, 1, max}], {t, 0, x}]; Rest[ CoefficientList[ Series[f[x], {x, 0, max}], x]*Range[0, max]!] (* Jean-François Alcover, Aug 07 2012, after Ralf Stephan *) CROSSREFS Cf. A032347, A046934. Sequence in context: A279567 A281784 A032347 * A329055 A148495 A150221 Adjacent sequences:  A032343 A032344 A032345 * A032347 A032348 A032349 KEYWORD nonn,nice,easy,eigen AUTHOR Joe K. Crump (joecr(AT)carolina.rr.com) EXTENSIONS Last digit of a(22) corrected by Jean-François Alcover, Aug 07 2012 STATUS approved

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Last modified April 8 14:29 EDT 2020. Contains 333314 sequences. (Running on oeis4.)