A253434 - OEIS

A253434

Number of (n+1) X (7+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.

%I #7 Dec 12 2018 09:28:20

%S 613,606,624,660,732,876,1164,1740,2892,5196,9804,19020,37452,74316,

%T 148044,295500,590412,1180236,2359884,4719180,9437772,18874956,

%U 37749324,75498060,150995532,301990476,603980364,1207960140,2415919692,4831838796

%N Number of (n+1) X (7+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.

%H R. H. Hardin, <a href="/A253434/b253434.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) - 2*a(n-2) for n>3.

%F Empirical: a(n) = 9*2^(n-1) + 588 for n>1.

%F Empirical g.f.: x*(613 - 1233*x + 32*x^2) / ((1 - x)*(1 - 2*x)). - _Colin Barker_, Dec 12 2018

%e Some solutions for n=4:

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

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

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

%Y Column 7 of A253435.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 31 2014