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A118988
Number of different values taken by the permanent of a symmetric real (+1,-1)-matrix of order n.
3
1, 2, 2, 4, 7, 15, 20, 62, 190, 771, 2073
OFFSET
0,2
CROSSREFS
Cf. A006125 (number of symmetric real (+1,-1)-matrices of order (n-1)).
Sequence in context: A300353 A049868 A120363 * A049904 A049906 A014265
KEYWORD
nonn,more
AUTHOR
Giovanni Resta, May 08 2006
EXTENSIONS
a(8)-a(9) from Minfeng Wang, Jun 20 2024
a(0)=1 prepended by Alois P. Heinz, Jun 21 2024
a(10) from Minfeng Wang, Sep 21 2024
STATUS
approved