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A222906 T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

%I A222906 #6 Jul 23 2025 03:14:34
%S A222906 1,1,2,1,4,5,4,7,14,15,5,25,45,75,51,14,92,373,767,411,187,17,403,
%T A222906 1202,7794,4909,2522,715,75,1710,18981,101398,180203,119393,15919,
%U A222906 2795,95,8021,82020,1346067,2117424,4320431,759891,103627,11051,411,36160
%N A222906 T(n,k)=Number of nXk 0..3 arrays with no more than floor(nXk/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
%C A222906 Table starts
%C A222906 ......1.........1............1................4.................5
%C A222906 ......2.........4............7...............25................92
%C A222906 ......5........14...........45..............373..............1202
%C A222906 .....15........75..........767.............7794............101398
%C A222906 .....51.......411.........4909...........180203...........2117424
%C A222906 ....187......2522.......119393..........4320431.........213112150
%C A222906 ....715.....15919.......759891........105327353........4854855483
%C A222906 ...2795....103627.....20299463.......2592612272......488736554328
%C A222906 ..11051....683480....130579169......64243363904....11422629770589
%C A222906 ..43947...4554799...3588643955....1600125512239..1152667562787040
%C A222906 .175275..30542304..23230932391...40022606753953.27237086853444410
%C A222906 .700075.205785953.647426033879.1004596097977296
%H A222906 R. H. Hardin, <a href="/A222906/b222906.txt">Table of n, a(n) for n = 1..125</a>
%e A222906 Some solutions for n=3 k=4
%e A222906 ..0..1..1..1....0..0..0..0....0..0..0..1....0..0..0..0....0..1..1..1
%e A222906 ..1..1..1..1....0..0..1..0....0..0..2..2....0..1..2..2....1..1..1..1
%e A222906 ..1..0..1..1....0..0..1..1....2..2..2..2....2..2..2..2....1..1..1..0
%Y A222906 Column 1 is A007581(n-1)
%Y A222906 Row 1 is A222372
%K A222906 nonn,tabl
%O A222906 1,3
%A A222906 _R. H. Hardin_ Mar 09 2013