A178025 - OEIS

A178025

Number of permutations of 4 copies of 1..n with no element e[i>=2]<e[1+floor((i-2)/5)] (5-way heap)

%I #3 Mar 31 2012 12:35:44

%S 1,19,2265,1130500,1023558900,2110942716750,8930744592735000

%N Number of permutations of 4 copies of 1..n with no element e[i>=2]<e[1+floor((i-2)/5)] (5-way heap)

%Y Simple 2-way heap A056971

%K nonn

%O 1,2

%A _R. H. Hardin_ May 17 2010