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A184376 T(n,k)=1/3 the number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock having at least two equal elements connected horizontally or vertically.

%I A184376 #7 Jul 22 2025 09:32:10
%S A184376 21,153,153,1107,2755,1107,8019,49235,49235,8019,58077,880781,2167173,
%T A184376 880781,58077,420633,15754461,95528423,95528423,15754461,420633,
%U A184376 3046491,281803871,4210059673,10378244309,4210059673,281803871,3046491,22064643
%N A184376 T(n,k)=1/3 the number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock having at least two equal elements connected horizontally or vertically.
%C A184376 Table starts
%C A184376 .........21............153...............1107....................8019
%C A184376 ........153...........2755..............49235..................880781
%C A184376 .......1107..........49235............2167173................95528423
%C A184376 .......8019.........880781...........95528423.............10378244309
%C A184376 ......58077.......15754461.........4210059673...........1127256514575
%C A184376 .....420633......281803871.......185547841629.........122443114867993
%C A184376 ....3046491.....5040682279......8177524177277.......13299774554091575
%C A184376 ...22064643....90163722073....360402692568245.....1444622701339019869
%C A184376 ..159806277..1612776998193..15883791500540967...156915034606615850427
%C A184376 .1157419449.28848073268443.700035935394350709.17044123945719790186817
%H A184376 R. H. Hardin, <a href="/A184376/b184376.txt">Table of n, a(n) for n = 1..144</a>
%e A184376 Some solutions for 4X3 with a(1,1)=0
%e A184376 ..0..2..0....0..0..2....0..2..1....0..2..1....0..1..0....0..1..2....0..1..0
%e A184376 ..0..0..0....0..0..2....0..0..1....0..0..1....2..1..0....0..1..0....2..2..2
%e A184376 ..2..0..1....2..2..2....1..2..1....2..2..1....0..1..1....0..2..2....0..1..2
%e A184376 ..2..0..2....1..0..0....1..0..1....2..2..1....1..1..2....1..2..0....1..1..0
%K A184376 nonn,tabl
%O A184376 1,1
%A A184376 _R. H. Hardin_ Jan 12 2011