Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #4 Dec 18 2015 18:17:16
%S 1,2,0,0,42,276,0,0,20340,216680,0,0,30693320,449345680,0,0,
%T 105796267920,1972495637280,0,0,696951215563680,15784392403940160,0,0,
%U 7817495632183997760,208339434598512497280,0,0
%N Number of n X n arrays of squares of integers, symmetric under 90 degree rotation, with all rows summing to 3.
%K nonn
%O 3,2
%A _R. H. Hardin_ Feb 09 2009