%I #8 Feb 03 2021 21:40:45

%S 1,3,31,2371,1084851,3680774301,91358224634433,17470072106054582211,

%T 26088526624958727703324771,310419652143758898175543447421953,

%U 29785621316391113552729016416250323294253

%N Number of n X n 0..2 arrays with row sums n and column sums n.

%H R. H. Hardin, <a href="/A172645/b172645.txt">Table of n, a(n) for n=1..14</a>

%Y Main diagonal of A334549.

%K nonn

%O 1,2

%A _R. H. Hardin_, Feb 06 2010