cp's OEIS Frontend

A195215 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 3 or less and triangles differing by a constant counted only once.

%I A195215 #7 Jul 22 2025 12:40:19
%S A195215 1,37,5453,3395245,9032683465,103565705397639,5137554141710397313,
%T A195215 1105495964728300359472149,1033611648181176182212080096433,
%U A195215 4204060119607140359160709072654583501
%N A195215 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 3 or less and triangles differing by a constant counted only once.
%C A195215 Column 3 of A195220
%e A195215 Some solutions for n=5
%e A195215 ...0...............0...............0...............0...............0
%e A195215 ..-3.-1............3..0...........-1.-1............0..3............2..1
%e A195215 ..-1.-2.-2.........2..1..3.........2.-1.-4.........1..2..4.........3..3..4
%e A195215 ...1..0..0.-3.....-1..2..3..2.....-1.-1.-2.-5......3..3..1..1......3..1..3..5
%e A195215 ...3..0.-2.-1..0...1..0..2..1..0...0.-2.-2.-2.-3...2..0..1..2.-1...2..0..3..5..7
%K A195215 nonn
%O A195215 1,2
%A A195215 _R. H. Hardin_ Sep 13 2011