%I #4 Nov 17 2015 15:31:36
%S 0,2,16,216,14852,1994830,591482528,510948245264,1135318355003028,
%T 6257173857277450930
%N Number of (n+1)X(n+1) arrays of permutations of 0..(n+1)^2-1 with each element having directed index change -1,1 -1,2 1,0 or 0,-1.
%C Diagonal of A264550.
%e Some solutions for n=4
%e ..1..5..6..4..8....1..5..3..4..7....1..2..3..4..7....1..2..3..4..7
%e ..0..7..2..3.12....0.10..2..9.12....0.10..8..9.12....0.10..8.11.12
%e .11.15.16.14..9...11..6.13..8.17....5..6.13.14.18....5..6.13.17..9
%e .10.20.18.13.23...16.20.18.21.14...16.11.20.21.23...16.20.18.21.14
%e .21.22.17.24.19...15.22.23.24.19...15.22.17.24.19...15.22.23.24.19
%Y Cf. A264550.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 17 2015