Search: id:A127888 Results 1-1 of 1 results found. %I A127888 %S A127888 0,478483200,6401339808768000,620429964386047303680000, %T A127888 265250626231132937174895820800000, %U A127888 371992180902371387782970387300352000000000 %N A127888 If X_1,...,X_n is a partition of a 6n-set X into 6-blocks then a(n) is equal to the number of permutations f of X such that f(X_i)<>X_i, (i=1,...n). %H A127888 Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets %F A127888 a(n)=sum((-720)^i*binomial(n,i)*(6*n-6*i)!,i=0..n). %e A127888 a(5)=265250626231132937174895820800000 %p A127888 a:=n->sum((-720)^i*binomial(n,i)*(6*n-6*i)!,i=0..n). %Y A127888 Sequence in context: A038819 A091677 A147717 this_sequence A072232 A011523 A101641 %Y A127888 Adjacent sequences: A127885 A127886 A127887 this_sequence A127889 A127890 A127891 %K A127888 nonn %O A127888 1,2 %A A127888 Milan R. Janjic (agnus(AT)blic.net), Apr 09 2007 Search completed in 0.001 seconds