A251403 - OEIS

%I #9 Nov 29 2018 10:37:34

%S 46,238,1230,6370,32954,170634,883018,4571514,23660362,122482746,

%T 633962570,3281695226,16986365322,87927675962,455129029834,

%U 2355889539450,12194590587914,63122652320442,326737675994954,1691282074795002

%N Number of (n+1) X (1+1) 0..2 arrays with every 2 X 2 subblock summing to a prime.

%H R. H. Hardin, <a href="/A251403/b251403.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) + 21*a(n-2) - 14*a(n-3) - 52*a(n-4) + 12*a(n-5).

%F Empirical g.f.: 2*x*(23 + 73*x - 106*x^2 - 222*x^3 + 54*x^4) / (1 - 2*x - 21*x^2 + 14*x^3 + 52*x^4 - 12*x^5). - _Colin Barker_, Nov 29 2018

%e Some solutions for n=4:

%e ..2..2....1..2....0..0....2..2....0..0....1..0....0..1....0..1....0..0....0..2

%e ..1..2....0..2....2..0....1..2....2..0....0..2....2..0....0..1....2..1....0..1

%e ..0..0....2..1....2..1....2..2....1..0....1..0....0..1....0..2....2..2....2..0

%e ..1..2....2..0....1..1....0..1....0..2....2..2....1..1....0..1....1..2....0..1

%e ..1..1....0..1....0..1....2..0....1..2....1..2....1..2....1..1....0..2....0..1

%Y Column 1 of A251410.

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 02 2014