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%I #6 Apr 23 2021 14:43:40
%S 1,16,76,593,4066,30474,224767,1677576,12501697,93326748,696648090,
%T 5201566740,38838190382,290002695764,2165445664904,16169462527006,
%U 120738141567615,901558501245777,6731990296360212,50268177842308933
%N Number of n X 4 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
%C Column 4 of A300923.
%H R. H. Hardin, <a href="/A300919/b300919.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) +36*a(n-2) -21*a(n-3) -346*a(n-4) -529*a(n-5) +29*a(n-6) +2597*a(n-7) +8260*a(n-8) +11611*a(n-9) +368*a(n-10) -35164*a(n-11) -81411*a(n-12) -86427*a(n-13) +5039*a(n-14) +175990*a(n-15) +304018*a(n-16) +197791*a(n-17) -229563*a(n-18) -828885*a(n-19) -1170749*a(n-20) -338874*a(n-21) +2113879*a(n-22) +5316893*a(n-23) +6600278*a(n-24) +3696989*a(n-25) -3617625*a(n-26) -12496428*a(n-27) -18323096*a(n-28) -16670814*a(n-29) -7337987*a(n-30) +6467136*a(n-31) +17584309*a(n-32) +22433854*a(n-33) +18734836*a(n-34) +10522849*a(n-35) +363725*a(n-36) -6880129*a(n-37) -10066510*a(n-38) -8745002*a(n-39) -5239909*a(n-40) -1424902*a(n-41) +1169952*a(n-42) +2171100*a(n-43) +1915618*a(n-44) +1076960*a(n-45) +248258*a(n-46) -100279*a(n-47) -235054*a(n-48) -157503*a(n-49) -105859*a(n-50) -35780*a(n-51) +7296*a(n-52) +17654*a(n-53) +9223*a(n-54) +5518*a(n-55) +1196*a(n-56) +720*a(n-57) -1030*a(n-58) -906*a(n-59) -38*a(n-60) -76*a(n-61) -32*a(n-62) +9*a(n-63) +13*a(n-64) +7*a(n-65) -a(n-66) for n > 68.
%e Some solutions for n=5
%e ..0..0..1..1. .0..0..1..1. .0..1..0..0. .0..0..1..1. .0..0..0..1
%e ..0..0..1..0. .0..0..1..1. .1..1..0..0. .0..1..0..1. .0..1..0..0
%e ..0..0..0..0. .0..1..1..1. .0..1..0..1. .0..1..1..1. .0..0..0..1
%e ..0..0..1..1. .0..0..1..0. .1..1..1..1. .0..0..0..1. .1..0..0..0
%e ..0..0..1..1. .1..0..0..0. .1..0..1..1. .1..0..1..1. .0..0..0..0
%Y Cf. A300923.
%K nonn
%O 1,2
%A _R. H. Hardin_, Mar 15 2018
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