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%I #7 May 10 2013 12:44:45
%S 0,0,0,0,20,240,1470,10640,83160,584640,4496030,42658440,371762820,
%T 3594871280,38650622010,396457108320,4330689250160,53963701424640,
%U 641211774798510,8205894865096280,113786291585124060
%N Number of degree-n permutations of order exactly 6.
%F E.g.f.: exp(x)-exp(x+1/2*x^2)-exp(x+1/3*x^3)+exp(x+1/2*x^2+1/3*x^3+1/6*x^6).
%t nn=21;Range[0,nn]!CoefficientList[Series[(Exp[x^6/6]-1)Exp[x+x^2/2+x^3/3]+(Exp[x^2/2]-1)(Exp[x^3/3]-1)Exp[x],{x,0,nn}],x]//Rest (* _Geoffrey Critzer_, Feb 04 2013 *)
%Y Cf. A000085, A001470, A001472, A052501, A053496-A053505, A001189, A001471, A001473, A061121-A061128.
%K easy,nonn
%O 1,5
%A _Vladeta Jovovic_, Apr 14 2001
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