A056990 Number of nonsingular n X n (-1,1)-matrices.
1, 2, 8, 192, 22272, 11550720, 25629327360, 236229525504000, 8858686914082897920, 1331751782100764385607680
Offset: 0
Links
- Eric Weisstein's World of Mathematics, Nonsingular Matrix.
Formula
a(n) = 2^(2*n-1) * A055165(n-1) for n>=1.
Extensions
a(5) from Winston C. Yang (winston(AT)cs.wisc.edu), Aug 26 2000
a(6)-a(8) computed from A055165 by David desJardins, Apr 22 2001
a(9) from Max Alekseyev, computed from A055165, Jan 15 2007
a(0)=1 prepended by Alois P. Heinz, May 29 2024