A301540 - OEIS

%I #4 Mar 23 2018 11:06:36

%S 21,86,374,1841,9037,47791,255406,1432328,8145489,46701775,269741883,

%T 1568279203,9153838956,53577605791,314145731065,1844204380914,

%U 10835966335712,63710021424647,374740321237045,2204822119962792

%N Number of nX7 0..1 arrays with every element equal to 0, 1 or 3 horizontally or vertically adjacent elements, with upper left element zero.

%C Column 7 of A301541.

%H R. H. Hardin, <a href="/A301540/b301540.txt">Table of n, a(n) for n = 1..156</a>

%e Some solutions for n=5

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

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

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

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

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

%Y Cf. A301541.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 23 2018