%I #6 Apr 21 2020 12:53:54
%S 0,8,158,2650,55854,1998526,157706284,32788533228,19802007716084,
%T 36574110002226508
%N Number of n X n 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly one mistake.
%C Diagonal of A278676.
%e Some solutions for n=4
%e ..1..1..0..0. .1..1..0..0. .0..0..1..1. .0..0..0..0. .1..0..0..0
%e ..1..1..0..0. .1..0..1..0. .1..0..1..1. .0..0..0..0. .0..1..1..0
%e ..1..1..1..0. .1..0..1..0. .1..1..1..0. .1..0..1..0. .1..1..1..0
%e ..1..1..0..0. .1..1..0..0. .1..1..1..1. .1..1..0..1. .1..1..1..0
%Y Cf. A278676.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 25 2016
|