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Number of n X 7 0..n*7-1 arrays with upper left zero and lower right n*7-1 and each element differing from its horizontal, vertical and antidiagonal neighbors by a power of two.
1

%I #6 Apr 26 2021 19:25:39

%S 456,1627,534268,19333806,7124418191,108447811968,618833411493090,

%T 793110858664665,1573398218250767384,57223609153517566156,

%U 204578625923507863105689,634520646697818868463969

%N Number of n X 7 0..n*7-1 arrays with upper left zero and lower right n*7-1 and each element differing from its horizontal, vertical and antidiagonal neighbors by a power of two.

%C Column 7 of A265601.

%H R. H. Hardin, <a href="/A265600/b265600.txt">Table of n, a(n) for n = 1..15</a>

%e Some solutions for n=2

%e ..0..8.10..9..8..7..9....0..2..1..3..5..7..9....0..8.10..6..5..7..9

%e ..4.12.11..7..9..5.13....1..3..5..1..9.11.13....4..6..8..7..6..5.13

%Y Cf. A265601.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 10 2015