OFFSET
0,3
LINKS
C. J. Everett and P. R. Stein, The asymptotic number of (0,1)-matrices with zero permanent, Disc. Math. 6 (1973), 29-34.
FORMULA
a(n) is asymptotic to n*(2^(n^2 - n + 1)). [Everett and Stein]
MATHEMATICA
a[ n_] := Count[Table[Permanent[Partition[a, n]], {a, Tuples[{0, 1}, n^2]}], 0]; (* Michael Somos, Aug 05 2018 *)
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Michael Somos, Oct 03 2003
EXTENSIONS
a(5) from Jaap Spies, Nov 02 2003
a(6) from Gordon F. Royle, Nov 03 2003
a(7) added by Geoffrey Critzer, Dec 19 2023 after Noam Zeilberger in A227414.
a(0)=0 prepended by Alois P. Heinz, Dec 19 2023
STATUS
approved