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A239340 T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or three plus the sum of the elements above it, modulo 4.

%I A239340 #6 Jun 02 2025 09:26:45
%S A239340 2,5,5,12,31,12,28,172,172,28,66,926,2187,926,66,156,5078,27341,27341,
%T A239340 5078,156,368,27861,346028,790681,346028,27861,368,868,152260,4360887,
%U A239340 22952323,22952323,4360887,152260,868,2048,832207,54774178,663249556
%N A239340 T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or three plus the sum of the elements above it, modulo 4.
%C A239340 Table starts
%C A239340 ....2.......5.........12.............28................66..................156
%C A239340 ....5......31........172............926..............5078................27861
%C A239340 ...12.....172.......2187..........27341............346028..............4360887
%C A239340 ...28.....926......27341.........790681..........22952323............663249556
%C A239340 ...66....5078.....346028.......22952323........1527488498.........101276030555
%C A239340 ..156...27861....4360887......663249556......101276030555.......15397080750829
%C A239340 ..368..152260...54774178....19117551262.....6693244281896.....2331550702010844
%C A239340 ..868..832207..688266175...550960518608...442014330398515...352742924096563362
%C A239340 .2048.4550810.8649330696.15873533676775.29178369838713161.53342694175522093768
%H A239340 R. H. Hardin, <a href="/A239340/b239340.txt">Table of n, a(n) for n = 1..180</a>
%F A239340 Empirical for column k:
%F A239340 k=1: a(n) = 2*a(n-1) +2*a(n-3)
%F A239340 k=2: [order 16]
%F A239340 k=3: [order 64]
%e A239340 Some solutions for n=3 k=4
%e A239340 ..2..0..2..0....2..0..2..0....2..1..2..0....0..2..0..1....2..0..0..2
%e A239340 ..0..0..2..2....3..1..3..2....2..2..0..0....0..0..2..2....3..1..0..0
%e A239340 ..2..1..2..0....3..1..3..2....0..0..3..1....0..2..2..3....2..2..2..2
%K A239340 nonn,tabl
%O A239340 1,1
%A A239340 _R. H. Hardin_, Mar 16 2014