A183617 - OEIS

A183617

1/120 the number of (n+1) X 5 0..4 arrays with every 2 X 2 subblock containing four distinct values.

%I #7 Mar 23 2023 07:59:37

%S 216,4992,115760,2708848,63632480,1498220176,35321033072,833329037376,

%T 19669285954672,464377424786608,10965243510496992,258942543673642320,

%U 6115202229118671536,144421327114372301632,3410825769986070048176

%N 1/120 the number of (n+1) X 5 0..4 arrays with every 2 X 2 subblock containing four distinct values.

%C Column 4 of A183622.

%H R. H. Hardin, <a href="/A183617/b183617.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 49*a(n-1)-749*a(n-2)+2986*a(n-3)+18914*a(n-4)-143912*a(n-5)-25696*a(n-6)+1494272*a(n-7)-1042432*a(n-8)-3600384*a(n-9)+917504*a(n-10)+393216*a(n-11).

%e Some solutions with the first square being 0123 for 3 X 5

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

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

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

%Y Cf. A183622.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 06 2011