|
%I #4 Dec 14 2013 06:17:40
%S 15272,341849,7655432,171455430,3839022704,85958825311,1924641376011,
%T 43093190215906,964865318375114,21603527637037559,483707247481446040,
%U 10830300554586216393,242492560693344416243,5429456145729472780602
%N Number of (1+2)X(n+2) 0..2 arrays with no increasing sequence of length 3 horizontally, vertically or antidiagonally downwards
%C Row 1 of A233602
%H R. H. Hardin, <a href="/A233603/b233603.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 26*a(n-1) -16*a(n-2) -1634*a(n-3) +2604*a(n-4) +36056*a(n-5) -49349*a(n-6) -329582*a(n-7) +280917*a(n-8) +1081611*a(n-9) -606669*a(n-10) -1800926*a(n-11) +659223*a(n-12) +1725796*a(n-13) -405251*a(n-14) -986564*a(n-15) +141685*a(n-16) +326475*a(n-17) -25199*a(n-18) -54329*a(n-19) +1736*a(n-20) +2831*a(n-21) +16*a(n-22) -64*a(n-23)
%e Some solutions for n=1
%e ..2..2..1....0..0..2....2..0..1....2..0..1....2..2..0....2..2..2....0..0..0
%e ..2..1..2....1..1..1....0..0..1....2..2..2....0..0..2....1..1..1....0..2..1
%e ..1..0..0....0..1..1....0..0..2....2..0..2....2..2..1....2..0..1....1..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 14 2013
| 