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A204978 T(n,k)=Number of nXk 0..2 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..2 introduced in row major order.

%I A204978 #8 Jul 22 2025 18:29:20
%S A204978 1,2,2,4,14,4,11,96,96,11,30,726,1217,726,30,82,5400,16813,16813,5400,
%T A204978 82,224,40344,226908,451468,226908,40344,224,612,301056,3074889,
%U A204978 11815256,11815256,3074889,301056,612,1672,2247264,41618941,311275169,594430765
%N A204978 T(n,k)=Number of nXk 0..2 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..2 introduced in row major order.
%C A204978 Table starts
%C A204978 ...1.......2.........4...........11.............30..............82
%C A204978 ...2......14........96..........726...........5400...........40344
%C A204978 ...4......96......1217........16813.........226908.........3074889
%C A204978 ..11.....726.....16813.......451468.......11815256.......311275169
%C A204978 ..30....5400....226908.....11815256......594430765.....30057359681
%C A204978 ..82...40344...3074889....311275169....30057359681...2924321664147
%C A204978 .224..301056..41618941...8202482914..1519010368414.284567725886961
%C A204978 .612.2247264.563504926.216132492162.76757855124562
%H A204978 R. H. Hardin, <a href="/A204978/b204978.txt">Table of n, a(n) for n = 1..84</a>
%e A204978 Some solutions for n=5 k=3
%e A204978 ..0..1..1....0..0..1....0..1..0....0..0..1....0..0..1....0..0..1....0..0..1
%e A204978 ..0..1..2....2..0..0....2..1..2....2..0..0....0..0..1....0..0..1....1..2..1
%e A204978 ..2..2..0....2..1..2....2..2..1....2..1..2....1..1..2....1..2..2....2..2..0
%e A204978 ..0..1..1....1..1..2....0..1..1....0..1..2....2..1..1....1..2..2....0..0..2
%e A204978 ..0..2..1....1..2..0....0..0..2....0..2..0....0..0..2....0..0..1....2..0..0
%Y A204978 Column 1 is A021006(n-3)
%Y A204978 Column 2 is A204699
%K A204978 nonn,tabl
%O A204978 1,2
%A A204978 _R. H. Hardin_ Jan 21 2012