# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a089179 Showing 1-1 of 1 %I A089179 #9 Jun 05 2019 09:46:26 %S A089179 1,2,6,20,85,402,2464,15752,119655,976190,9331894,91769988,1077214879, %T A089179 12570658310,168390947820,2337860163248,35513649943201, %U A089179 544140329564898,9660558198790510,166372364728477220 %N A089179 Number of equivalence classes of permutations of n letters, where the relation is that f and g are equivalent if every cycle of f is a power of some cycle of g. %H A089179 Albert Nijenhuis, Solution to Problem 5932, Amer. Math. Monthly, 82 (1975), pp. 86-87. %H A089179 R. P. Stanley, Problem 5932, Amer. Math. Monthly, 80 (1973), p. 949. %F A089179 E.g.f. x*exp(Sum( x^n/(n*phi(n)), n=1..infinity )) (phi is Euler's totient function). a(n) = n* A003510(n-1). - _Vladeta Jovovic_, Apr 15 2006 %t A089179 yy[nn_] := CoefficientList[Normal[Series[Exp[Sum[x^n t[n]/(n), {n, 1, nn}]], {x, 0, nn}]], x]; zz[nn_] := Table[Simplify[yy[nn][[m]] m! ], {m, 1, nn}]; zz[10] (* will then give the first 10 values *) %K A089179 easy,nonn %O A089179 1,2 %A A089179 Herbert S. Wilf, Dec 08 2003 %E A089179 More terms from _Vladeta Jovovic_, Apr 15 2006 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE