A297989 - OEIS

%I #4 Jan 10 2018 07:34:00

%S 2,49,146,466,1446,4648,14888,47399,150849,480015,1528351,4868127,

%T 15504952,49377480,157242432,500744003,1594669951,5078421202,

%U 16172807093,51503968299,164019559229,522337092408,1663436972579,5297389242128

%N Number of nX4 0..1 arrays with every element equal to 1, 2, 3 or 6 king-move adjacent elements, with upper left element zero.

%C Column 4 of A297993.

%H R. H. Hardin, <a href="/A297989/b297989.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-1) -6*a(n-2) +2*a(n-3) -5*a(n-4) +10*a(n-5) -19*a(n-6) -30*a(n-7) +29*a(n-8) +61*a(n-9) +81*a(n-10) -91*a(n-11) -78*a(n-12) -35*a(n-13) +86*a(n-14) +10*a(n-15) -35*a(n-16) -23*a(n-17) +16*a(n-18) +37*a(n-19) -32*a(n-20) +14*a(n-21) +6*a(n-22) -8*a(n-23) +4*a(n-24) for n>27

%e Some solutions for n=7

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

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

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

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

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

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

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

%Y Cf. A297993.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 10 2018