This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A088672 #29 Dec 19 2023 21:27:13
%S A088672 0,1,9,265,27713,10363361,13906734081,68121583929729
%N A088672 Number of n X n (0,1)-matrices with zero permanent.
%H A088672 C. J. Everett and P. R. Stein, <a href="https://doi.org/10.1016/0012-365X(73)90034-4">The asymptotic number of (0,1)-matrices with zero permanent</a>, Disc. Math. 6 (1973), 29-34.
%H A088672 <a href="/index/Mat#binmat">Index entries for sequences related to binary matrices</a>
%F A088672 a(n) is asymptotic to n*(2^(n^2 - n + 1)). [Everett and Stein]
%F A088672 a(n) = A002416(n) - A227414(n). - _Geoffrey Critzer_, Dec 19 2023
%t A088672 a[ n_] := Count[Table[Permanent[Partition[a, n]], {a, Tuples[{0, 1}, n^2]}], 0]; (* _Michael Somos_, Aug 05 2018 *)
%Y A088672 Cf. A089479, A089482, A227414.
%K A088672 nonn,more,hard
%O A088672 0,3
%A A088672 _Michael Somos_, Oct 03 2003
%E A088672 a(5) from _Jaap Spies_, Nov 02 2003
%E A088672 a(6) from _Gordon F. Royle_, Nov 03 2003
%E A088672 a(7) added by _Geoffrey Critzer_, Dec 19 2023 after Noam Zeilberger in A227414.
%E A088672 a(0)=0 prepended by _Alois P. Heinz_, Dec 19 2023