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%I #15 Feb 25 2018 15:49:12
%S 1,34,455,3626,20580,91728,340956,1099890,3166449,8302294,20131111,
%T 45677996,97894160,199645824,389817072,732389580,1329624009,
%U 2340785370,4008235231,6693165094,10923775940,17459327600,27374197500,42166911150,63900046665,95377983246
%N a(n) = (n+1)(n+2)^2*(n+3)^3*(n+4)^2*(n+5)(n^2 + 6n + 10)/86400.
%C Kekulé numbers for certain benzenoids.
%D S. J. Cyvin and I. Gutman, Kekulé structures in benzenoid hydrocarbons, Lecture Notes in Chemistry, No. 46, Springer, New York, 1988 (p. 229).
%H T. D. Noe, <a href="/A107917/b107917.txt">Table of n, a(n) for n = 0..1000</a>
%F G.f.: (x^6+22*x^5+113*x^4+190*x^3+113*x^2+22*x+1)/(x-1)^12. - _Colin Barker_, Jun 06 2012
%p a:=n->(1/86400)*(n+1)*(n+2)^2*(n+3)^3*(n+4)^2*(n+5)*(n^2+6*n+10): seq(a(n),n=0..27);
%K nonn,easy
%O 0,2
%A _Emeric Deutsch_, Jun 12 2005