A234226 - OEIS

%I #6 Jun 19 2022 02:14:44

%S 582144,1123724,2264904,5162984,12178344,31418264,83324136,236748824,

%T 690049704,2128516184,6731960424,22318060184,75732130344,266822847704,

%U 958417428456,3541285003544,13272289633704,50766360814424

%N Number of (n+1) X (7+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3 (constant-stress 1 X 1 tilings).

%H R. H. Hardin, <a href="/A234226/b234226.txt">Table of n, a(n) for n = 1..23</a>

%F Empirical: a(n) = 10*a(n-1) +16*a(n-2) -460*a(n-3) +789*a(n-4) +7170*a(n-5) -23944*a(n-6) -39920*a(n-7) +246076*a(n-8) -38440*a(n-9) -1115136*a(n-10) +1151040*a(n-11) +2005056*a(n-12) -3657600*a(n-13) -331776*a(n-14) +3456000*a(n-15) -1658880*a(n-16).

%e Some solutions for n=1:

%e   1 1 2 1 2 4 2 3    1 0 3 4 0 4 0 4    0 2 3 3 2 3 2 0

%e   1 4 2 4 2 1 2 0    1 3 3 1 0 1 0 1    1 0 4 1 3 1 3 4

%Y Column 7 of A234227.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 21 2013