%I A033306
%S A033306 1,1,1,2,2,2,5,6,6,5,15,20,24,20,15,52,75,100,100,75,52,203,312,450,500,
%T A033306 450,312,203,877,1421,2184,2625,2625,2184,1421,877,4140,7016,11368,
%U A033306 14560,15750,14560,11368,7016,4140,21147,37260,63144,85260,98280,98280
%N A033306 Triangle of coefficients of ordered cycle-index polynomials: T(n,k) =
binomial(n,k)*Bell(k)*Bell(n-k).
%D A033306 J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p.
80.
%F A033306 E.g.f.: exp(exp(x*y)+exp(x)-2).
%e A033306 1; 1,1; 2,2,2; 5,6,6,5; 15,20,24,20,15; 52,75,100,100,75,5; ...
%Y A033306 Cf. A000110, row sums give A001861.
%Y A033306 Columns include A000110 and A052889.
%Y A033306 Sequence in context: A066835 A123953 A097006 this_sequence A136347 A162145
A145876
%Y A033306 Adjacent sequences: A033303 A033304 A033305 this_sequence A033307 A033308
A033309
%K A033306 nonn,tabl,easy
%O A033306 0,4
%A A033306 N. J. A. Sloane (njas(AT)research.att.com).
%E A033306 Edited by Vladeta Jovovic (vladeta(AT)eunet.rs), Sep 17 2003
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