A305484 - OEIS

%I #6 May 12 2023 15:11:09

%S 1,14,19,27,137,295,570,2026,4727,10623,31695,77554,186678,514389,

%T 1288865,3207903,8513828,21596662,54628207,142471209,363676271,

%U 927239206,2398775556,6143042745,15724343029,40529736309,103968954572,266660435630

%N Number of n X 3 0..1 arrays with every element unequal to 1, 2, 3, 6 or 8 king-move adjacent elements, with upper left element zero.

%C Column 3 of A305489.

%H R. H. Hardin, <a href="/A305484/b305484.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) +4*a(n-2) +11*a(n-3) -9*a(n-4) -39*a(n-5) -31*a(n-6) -4*a(n-7) +37*a(n-8) +19*a(n-9) +18*a(n-10) -2*a(n-11) -4*a(n-12) -16*a(n-13) -8*a(n-14) for n>16.

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A305489.

%K nonn

%O 1,2

%A _R. H. Hardin_, Jun 02 2018