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%I #4 Mar 08 2014 08:48:27
%S 3,7,7,15,41,15,31,203,203,31,63,955,2365,955,63,127,4393,25601,25601,
%T 4393,127,255,20015,270671,638779,270671,20015,255,511,90841,2827709,
%U 15482441,15482441,2827709,90841,511,1023,411621,29422487,370847909
%N T(n,k)=Number of nXk 0..3 arrays with no element equal to two plus the sum of elements to its left or two plus the sum of the elements above it, modulo 4
%C Table starts
%C ....3.......7.........15............31...............63..................127
%C ....7......41........203...........955.............4393................20015
%C ...15.....203.......2365.........25601...........270671..............2827709
%C ...31.....955......25601........638779.........15482441............370847909
%C ...63....4393.....270671......15482441........860394281..........47194836429
%C ..127...20015....2827709.....370847909......47194836429........5929702056895
%C ..255...90841...29422487....8839918663....2576820346901......741313154055591
%C ..511..411621..305525459..210298050207..140374233864007....92478950275376419
%C .1023.1863915.3170576253.4998886061169.7641515368274447.11527212881627494067
%H R. H. Hardin, <a href="/A238997/b238997.txt">Table of n, a(n) for n = 1..180</a>
%F Empirical for column k:
%F k=1: a(n) = 3*a(n-1) -2*a(n-2)
%F k=2: [order 9]
%F k=3: [order 35]
%e Some solutions for n=3 k=4
%e ..3..3..1..3....1..0..1..1....3..3..1..3....0..1..1..3....0..1..1..1
%e ..0..3..0..2....0..3..2..0....0..3..2..2....0..1..0..2....1..0..1..2
%e ..3..2..0..1....1..2..2..2....0..3..2..2....0..3..2..0....0..1..2..2
%Y Column 1 is A000225(n+1)
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_, Mar 08 2014