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Number of nX4 0..1 arrays with each 1 adjacent to 2 or 4 king-move neighboring 1s.
1

%I #4 Dec 03 2017 07:10:29

%S 1,21,70,204,997,4102,15399,63267,258493,1030120,4156150,16818617,

%T 67740232,273149847,1102534609,4447180671,17938365350,72372158734,

%U 291962906495,1177806200038,4751540115373,19168723999639,77330236093551

%N Number of nX4 0..1 arrays with each 1 adjacent to 2 or 4 king-move neighboring 1s.

%C Column 4 of A296039.

%H R. H. Hardin, <a href="/A296035/b296035.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +2*a(n-2) +25*a(n-3) -43*a(n-4) -60*a(n-5) -170*a(n-6) +105*a(n-7) +326*a(n-8) +30*a(n-9) -197*a(n-10) -2*a(n-11) +223*a(n-12) -11*a(n-13) -102*a(n-14) -2*a(n-15) +12*a(n-16) +2*a(n-17)

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A296039.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 03 2017