login
Number of n X 2 0..n+2-2 arrays with upper left zero and lower right n+2-2 and each element differing from its diagonal and antidiagonal neighbors by one or two.
1

%I #6 Oct 18 2021 13:39:10

%S 1,6,36,366,4900,55800,970225,11095448,204833344,1934752250,

%T 44951208289,364393934784,10048532283364,66162689956152,

%U 2276670647380900,12030558414011074,521323759854121156,2167321703073344910

%N Number of n X 2 0..n+2-2 arrays with upper left zero and lower right n+2-2 and each element differing from its diagonal and antidiagonal neighbors by one or two.

%C Column 2 of A265480.

%H R. H. Hardin, <a href="/A265474/b265474.txt">Table of n, a(n) for n = 1..202</a>

%e Some solutions for n=4

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

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

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

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

%Y Cf. A265480.

%K nonn

%O 1,2

%A _R. H. Hardin_, Dec 09 2015