cp's OEIS Frontend

A328001 T(n, k) = k!*(n-k)!/(floor(k/2)!*floor((n-k)/2)!)^2. Triangle read by rows, 0 <= k <= n.

%I A328001 #9 Oct 19 2019 10:49:11
%S A328001 1,1,1,2,1,2,6,2,2,6,6,6,4,6,6,30,6,12,12,6,30,20,30,12,36,12,30,20,
%T A328001 140,20,60,36,36,60,20,140,70,140,40,180,36,180,40,140,70,630,70,280,
%U A328001 120,180,180,120,280,70,630,252,630,140,840,120,900,120,840,140,630,252
%N A328001 T(n, k) = k!*(n-k)!/(floor(k/2)!*floor((n-k)/2)!)^2. Triangle read by rows, 0 <= k <= n.
%F A328001 T(n, k) = s(k)*s(n-k) where s(n) = A056040(n).
%e A328001                                1;
%e A328001                               1, 1;
%e A328001                             2, 1, 2;
%e A328001                            6, 2, 2, 6;
%e A328001                          6, 6, 4, 6, 6;
%e A328001                       30, 6, 12, 12, 6, 30;
%e A328001                    20, 30, 12, 36, 12, 30, 20;
%e A328001                 140, 20, 60, 36, 36, 60, 20, 140;
%e A328001              70, 140, 40, 180, 36, 180, 40, 140, 70;
%e A328001          630, 70, 280, 120, 180, 180, 120, 280, 70, 630;
%p A328001 T := (n, k) -> k!*(n-k)!/(iquo(k, 2)!*iquo(n-k, 2)!)^2:
%p A328001 seq(seq(T(n,k), k=0..n), n=0..10);
%Y A328001 Row sums in A328000. Central column in A327998.
%Y A328001 Cf. A056040.
%K A328001 tabl,nonn
%O A328001 0,4
%A A328001 _Peter Luschny_, Oct 01 2019