%I A143357
%S A143357 0,0,0,0,0,2,12,70,448,3298,27490,255876,2631876,29652480,363242880,
%T A143357 4807626352,68375130352,1040021719578,16848351857178,289631191449600,
%U A143357 5266021662720000,100970241446066086,2036233202495666086
%N A143357 Floor((n-1)!/[n(n+1)]).
%C A143357 All terms are even.
%D A143357 T. Andreescu, D. Andrica and Z. Feng, 104 Number Theory Problems (from 
               the training of the USA IMO team), Birkhauser, Boston, 2007, Introductory 
               problem # 50, pp. 82,126,127.
%p A143357 seq(floor(factorial(n-1)/(n*(n+1))),n=1..25);
%Y A143357 Sequence in context: A001542 A059229 A001251 this_sequence A012426 A012421 
               A012381
%Y A143357 Adjacent sequences: A143354 A143355 A143356 this_sequence A143358 A143359 
               A143360
%K A143357 nonn
%O A143357 1,6
%A A143357 Emeric Deutsch (deutsch(AT)duke.poly.edu), Aug 11 2008