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A215903 Number of diagonal and antidiagonal neighbor colorings of the even squares of an n X 7 array with new integer colors introduced in row major order.

%I A215903 #5 Jun 19 2025 21:25:12
%S A215903 15,203,84550,14050312,37060769357,18383354944364,148049909203591059,
%T A215903 152834703746357948488,2765650341438362598776986,
%U A215903 4971673449387903153569761420,170381714096217475684749198312607
%N A215903 Number of diagonal and antidiagonal neighbor colorings of the even squares of an n X 7 array with new integer colors introduced in row major order.
%C A215903 Column 7 of A215904.
%e A215903 Some solutions for n=3
%e A215903 ..0..x..1..x..2..x..3....0..x..1..x..2..x..3....0..x..0..x..1..x..2
%e A215903 ..x..4..x..4..x..5..x....x..4..x..5..x..4..x....x..3..x..4..x..5..x
%e A215903 ..6..x..6..x..0..x..1....0..x..0..x..0..x..3....6..x..1..x..0..x..2
%Y A215903 Cf. A215904.
%K A215903 nonn
%O A215903 1,1
%A A215903 _R. H. Hardin_, Aug 26 2012