%I #8 May 08 2020 18:22:18
%S 1,2,8,64,1024,28217,1146419,62951431,4451407563,392447922178,
%T 42102440864054,5391561047209898,811314950514676762,
%U 141599096294933832181,28348376853054890615951,6448749608634353498219753,1653216120840296892595307251,474197636984335589673286631814
%N Number of n X n symmetric binary matrices with no row sum greater than 4.
%H Andrew Howroyd, <a href="/A139680/b139680.txt">Table of n, a(n) for n = 0..40</a>
%Y Column k=4 of A334548.
%K nonn
%O 0,2
%A _R. H. Hardin_, Jun 13 2008
%E Terms a(13) and beyond from _Andrew Howroyd_, May 08 2020