A118992 Number of real n X n invertible symmetric (+1,-1) matrices.

2, 4, 32, 512, 16896, 1190144, 163899904

Offset

1,1

Links

Table of n, a(n) for n=1..7.

Crossrefs

Cf. A056990, A086899, A056989.A118990.

Sequence in context: A134958 A101460 A304862 * A012509 A062740 A336832

Adjacent sequences: A118989 A118990 A118991 * A118993 A118994 A118995

Keyword

nonn,more

Author

Giovanni Resta, May 08 2006

Status

approved