login
Number of different values taken by the permanent of a real nonsingular (0,1)-matrix of order n.
3

%I #4 Mar 31 2012 14:40:20

%S 1,1,3,9,31,149

%N Number of different values taken by the permanent of a real nonsingular (0,1)-matrix of order n.

%C This sequence was first provided by _Jaap Spies_.

%e a(4)=9 because the permanents of non-singular 4 X 4 (0,1)-matrices can take the

%e values 1,2,..,7,9,11.

%Y A055165, A089480 give occurrence counts for permanents of non-singular (0, 1)-matrices, A089476 different permanents of singular (0, 1)-matrices.

%K more,nonn

%O 1,3

%A _Hugo Pfoertner_, Nov 11 2003

%E a(6) from _Jaap Spies_, Nov 12 2003