cp's OEIS Frontend

A195253 Number of lower triangles of a 7X7 0..n array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by two or less.

%I A195253 #7 Jul 22 2025 12:42:55
%S A195253 268435456,22876792454961,254948725307650,786909681200387,
%T A195253 1479091549959182,2226347741716207,2987571816007840,3751562406061261,
%U A195253 4515974674903982,5280435818615649,6044900876514412,6809366105107111
%N A195253 Number of lower triangles of a 7X7 0..n array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by two or less.
%C A195253 Row 7 of A195248
%H A195253 R. H. Hardin, <a href="/A195253/b195253.txt">Table of n, a(n) for n = 1..200</a>
%F A195253 Empirical: a(n) = 764465228592699*n - 2364216638005277 for n>10
%e A195253 Some solutions for n=5
%e A195253 ..3..............2..............5..............0..............5
%e A195253 ..4.5............3.4............4.3............2.0............3.3
%e A195253 ..4.4.3..........5.4.5..........2.4.4..........0.2.0..........2.2.4
%e A195253 ..2.3.2.4........5.5.4.4........3.3.2.4........2.2.2.0........1.2.3.2
%e A195253 ..3.3.3.3.4......3.4.4.2.3......3.4.3.4.3......2.1.0.1.1......0.2.4.4.2
%e A195253 ..3.3.1.2.4.4....2.4.3.2.2.1....3.4.5.3.2.2....0.1.2.1.1.2....0.2.3.3.4.4
%e A195253 ..3.2.2.3.4.5.4..2.2.2.2.3.1.1..3.3.3.3.2.1.1..1.2.3.2.0.1.0..2.2.1.3.3.5.3
%K A195253 nonn
%O A195253 1,1
%A A195253 _R. H. Hardin_ Sep 13 2011