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Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 0 vertically
1

%I #5 Mar 31 2012 12:37:17

%S 9,81,351,1521,8463,47089,241087,1234321,6520459,34445161,179832029,

%T 938870881,4924284469,25827382681,135217499129,707921987161,

%U 3708936179293,19431812871409,101777874172609,533081279633809

%N Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 0 1 0 vertically

%C Row 4 of A207426

%H R. H. Hardin, <a href="/A207428/b207428.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +42*a(n-3) +338*a(n-4) +396*a(n-5) +1030*a(n-6) -2344*a(n-7) -26833*a(n-8) -38303*a(n-9) -63202*a(n-10) +52598*a(n-11) +985438*a(n-12) +1396288*a(n-13) +1115284*a(n-14) -1106178*a(n-15) -18477389*a(n-16) -25263353*a(n-17) -3049142*a(n-18) +22326584*a(n-19) +174876704*a(n-20) +237470328*a(n-21) -39378634*a(n-22) -214045948*a(n-23) -945656665*a(n-24) -1307385407*a(n-25) +307355250*a(n-26) +1045889236*a(n-27) +3162966504*a(n-28) +4555026416*a(n-29) -871998610*a(n-30) -2799326238*a(n-31) -6757086963*a(n-32) -10396330247*a(n-33) +1059472092*a(n-34) +4057077276*a(n-35) +9160267840*a(n-36) +15560256508*a(n-37) -237781588*a(n-38) -2626258574*a(n-39) -7575853071*a(n-40) -14895330403*a(n-41) -528389710*a(n-42) -340236834*a(n-43) +3585419896*a(n-44) +8683553694*a(n-45) +272258332*a(n-46) +1521488072*a(n-47) -955290301*a(n-48) -2840729543*a(n-49) +86640816*a(n-50) -835851548*a(n-51) +201803584*a(n-52) +443470096*a(n-53) -53983872*a(n-54) +176842688*a(n-55) -41717504*a(n-56) -21092864*a(n-57) +2904064*a(n-58) -11999232*a(n-59) +3026944*a(n-60) +176128*a(n-61) +245760*a(n-63) -65536*a(n-64)

%e Some solutions for n=4

%e ..1..0..1..1....1..1..1..1....1..0..1..1....1..1..0..1....1..0..1..1

%e ..1..0..1..1....1..1..1..0....0..1..1..1....1..1..0..1....0..0..1..1

%e ..0..0..1..1....1..0..1..1....0..1..1..1....1..0..0..1....0..0..1..1

%e ..1..0..0..1....1..1..0..1....0..0..1..1....1..0..0..1....0..0..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 17 2012