cp's OEIS Frontend

A208302 Number of 2Xn nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal or antidiagonal neighbor (colorings ignoring permutations of colors).

%I A208302 #7 Jun 02 2025 07:43:27
%S A208302 2,5,42,602,12840,373780,14050312,656404264,37060650272,2475181138384,
%T A208302 192262536609952,17131843186425504,1731360533569170048,
%U A208302 196551307092757144384,24860319276726031245440,3478554309451804194287232
%N A208302 Number of 2Xn nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any horizontal or antidiagonal neighbor (colorings ignoring permutations of colors).
%C A208302 Row 2 of A208301
%H A208302 R. H. Hardin, <a href="/A208302/b208302.txt">Table of n, a(n) for n = 1..21</a>
%e A208302 Some solutions for n=4
%e A208302 ..0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1
%e A208302 ..2..3..4..2....2..1..2..0....2..1..0..3....0..1..0..1....0..1..0..2
%K A208302 nonn
%O A208302 1,1
%A A208302 _R. H. Hardin_ Feb 25 2012