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%I #5 Mar 31 2012 12:36:29
%S 1,2,10,160,152,790,2724,6242,26422,91756,281296,990140,3437208,
%T 11190922,37836768,129296206,433975472,1455029298,4951850734,
%U 16696765546,56134653324,190052231444,641906625424,2162290128232,7306324921304
%N Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,1,0,0 for x=0,1,2,3,4
%C Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
%C Column 4 of A197317
%H R. H. Hardin, <a href="/A197313/b197313.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) +4*a(n-2) +6*a(n-3) -15*a(n-4) -14*a(n-5) +158*a(n-6) -75*a(n-7) -580*a(n-8) -544*a(n-9) +2442*a(n-10) -6108*a(n-11) -15674*a(n-12) +30424*a(n-13) +10460*a(n-14) -97388*a(n-15) +56218*a(n-16) +441502*a(n-17) -118178*a(n-18) -91784*a(n-19) +1837648*a(n-20) -170043*a(n-21) -3747640*a(n-22) -1924708*a(n-23) -22657*a(n-24) -7945855*a(n-25) -5336633*a(n-26) +10486980*a(n-27) +4002672*a(n-28) +5025718*a(n-29) +20403048*a(n-30) +11494725*a(n-31) +10614083*a(n-32) +10490910*a(n-33) +12687980*a(n-34) +9374913*a(n-35) -28487361*a(n-36) +8294976*a(n-37) +25580308*a(n-38) -60503291*a(n-39) -25248918*a(n-40) +13942686*a(n-41) -39639005*a(n-42) -37284559*a(n-43) -23466156*a(n-44) +22878562*a(n-45) +24899973*a(n-46) -31530561*a(n-47) +19180134*a(n-48) +36753693*a(n-49) -12016805*a(n-50) -3178342*a(n-51) +3297937*a(n-52) -4547374*a(n-53) +682965*a(n-54) -5465642*a(n-55) -4279697*a(n-56) +1150329*a(n-57) -2645817*a(n-58) +651720*a(n-59) +1143254*a(n-60) -684618*a(n-61) +266863*a(n-62) -143688*a(n-63) +60718*a(n-64) +108490*a(n-65) -45708*a(n-66) +14734*a(n-67) -10054*a(n-68) +2290*a(n-69) +1464*a(n-70) -1056*a(n-71) -16*a(n-72) -160*a(n-73) +48*a(n-74) for n>75
%e Some solutions containing all values 0 to 4 for n=5
%e ..0..1..1..0....0..1..1..0....1..2..1..1....0..1..1..2....1..2..1..0
%e ..1..2..0..3....3..0..2..1....1..0..3..0....3..0..2..1....1..0..1..2
%e ..1..0..4..0....0..4..0..1....0..4..0..1....0..4..0..1....0..4..0..1
%e ..2..1..0..1....1..0..3..0....3..0..2..1....1..0..1..2....3..0..2..1
%e ..0..1..2..1....1..2..1..1....0..1..1..0....1..2..1..0....0..1..1..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 13 2011
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