A162117 - OEIS

A162117

Number of n X n symmetric binary arrays with rows, considered as graycode numbers, in strictly increasing order, and no more than 9 ones in any row or column

%I #4 Dec 18 2015 18:17:23

%S 2,4,9,56,499,8000,207554,9382078,732814910,100881440613,

%T 23970739627607,9428485931810668

%N Number of n X n symmetric binary arrays with rows, considered as graycode numbers, in strictly increasing order, and no more than 9 ones in any row or column

%K nonn

%O 1,1

%A _R. H. Hardin_ Jun 25 2009