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%I #6 Apr 21 2020 12:55:10
%S 0,0,66,30772,9317846,4026240722,3637198028018,8472288445687482,
%T 56864856173457018228,1168082099198500119983316
%N Number of n X n 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly three mistakes.
%C Diagonal of A278855.
%e Some solutions for n=4
%e ..1..1..1..0. .1..1..0..0. .1..0..1..1. .1..1..1..0. .1..1..1..0
%e ..1..0..1..1. .1..1..0..0. .0..1..1..0. .1..0..1..1. .1..1..0..1
%e ..0..0..0..0. .0..1..0..1. .0..0..0..1. .0..0..1..1. .1..0..0..1
%e ..1..0..1..0. .1..0..1..0. .0..1..1..1. .1..1..1..0. .0..1..1..1
%Y Cf. A278855.
%K nonn
%O 1,3
%A _R. H. Hardin_, Nov 29 2016