A302461 - OEIS

%I #4 Apr 08 2018 10:03:39

%S 4,2,18,8,44,56,140,364,764,2352,5612,16144,42324,116260,314408,

%T 853216,2319700,6290064,17095288,46394920,126019004,342168972,

%U 929215108,2523394628,6852508984,18609263140,50535852808,137239321084,372695225548

%N Number of 3Xn 0..1 arrays with every element equal to 0, 2, 3 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

%C Row 3 of A302460.

%H R. H. Hardin, <a href="/A302461/b302461.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +10*a(n-2) -15*a(n-3) -46*a(n-4) +49*a(n-5) +121*a(n-6) -95*a(n-7) -193*a(n-8) +123*a(n-9) +187*a(n-10) -126*a(n-11) -96*a(n-12) +78*a(n-13) +20*a(n-14) -24*a(n-15) +6*a(n-16) +20*a(n-17) -4*a(n-19) for n>20

%e Some solutions for n=5

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

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

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

%Y Cf. A302460.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 08 2018