A234676 - OEIS

%I #6 Jun 20 2022 18:42:02

%S 1264,2924,6328,17312,43240,129848,354856,1129256,3265864,10806344,

%T 32397928,110161352,338146120,1172415368,3657091816,12860973896,

%U 40576496584,144194315144,458737409128,1642863057992,5259197091400

%N Number of (n+1) X (3+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings).

%H R. H. Hardin, <a href="/A234676/b234676.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +47*a(n-2) -200*a(n-3) -901*a(n-4) +4204*a(n-5) +8957*a(n-6) -48440*a(n-7) -47194*a(n-8) +334096*a(n-9) +101948*a(n-10) -1410080*a(n-11) +170136*a(n-12) +3549696*a(n-13) -1446912*a(n-14) -4861440*a(n-15) +2954880*a(n-16) +2764800*a(n-17) -2073600*a(n-18).

%e Some solutions for n=5:

%e   5 2 4 1     0 1 0 3     1 4 2 5     5 5 5 5     0 3 0 1

%e   3 5 2 4     5 1 5 3     2 0 3 1     5 0 5 0     4 2 4 0

%e   4 1 3 0     2 3 2 5     1 4 2 5     3 3 3 3     0 3 0 1

%e   2 4 1 3     5 1 5 3     2 0 3 1     0 5 0 5     4 2 4 0

%e   4 1 3 0     0 1 0 3     1 4 2 5     2 2 2 2     1 4 1 2

%e   2 4 1 3     5 1 5 3     3 1 4 2     5 0 5 0     4 2 4 0

%Y Column 3 of A234681.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 29 2013