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A241249 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4.

%I A241249 #6 Jun 02 2025 10:01:48
%S A241249 3,5,17,39,87,212,488,1134,2644,6118,14205,32964,76395,177149,410798,
%T A241249 952422,2208198,5120116,11871494,27525169,63821315,147978217,
%U A241249 343107782,795547902,1844596244,4276972393,9916824861,22993686321,53314396437
%N A241249 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4.
%C A241249 Column 2 of A241255
%H A241249 R. H. Hardin, <a href="/A241249/b241249.txt">Table of n, a(n) for n = 1..210</a>
%F A241249 Empirical: a(n) = 3*a(n-2) +14*a(n-3) +5*a(n-4) -28*a(n-5) -89*a(n-6) -50*a(n-7) +93*a(n-8) +303*a(n-9) +214*a(n-10) -113*a(n-11) -561*a(n-12) -468*a(n-13) -47*a(n-14) +584*a(n-15) +499*a(n-16) +142*a(n-17) -359*a(n-18) -96*a(n-19) -23*a(n-20) +128*a(n-21) -102*a(n-22) -99*a(n-23) -119*a(n-24) +32*a(n-25) +82*a(n-26) +113*a(n-27) +50*a(n-28) -7*a(n-29) -42*a(n-30) -20*a(n-31) +a(n-32) +4*a(n-33) +a(n-34) for n>37
%e A241249 Some solutions for n=4
%e A241249 ..3..3....3..3....2..2....2..2....2..2....3..3....3..2....2..2....3..3....2..2
%e A241249 ..2..1....2..2....3..1....3..1....3..1....2..1....0..3....3..1....2..2....3..1
%e A241249 ..3..1....0..2....0..2....3..1....3..2....0..2....0..2....3..1....3..2....2..1
%e A241249 ..3..3....3..2....3..3....3..2....3..2....0..3....0..2....2..1....3..1....2..2
%K A241249 nonn
%O A241249 1,1
%A A241249 _R. H. Hardin_, Apr 18 2014