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 A369285 #16 Jan 24 2024 18:33:08
%S A369285 1,1,0,4,12,72,522,4386,42360,465792,5697552,77229216,1145762400,
%T A369285 18485254536,322206163200,6033964218720,120830927523240,
%U A369285 2576515514434920,58285369894027440,1394212928447354640,35160926971256369400,932396530226753051160,25936228654879236020640
%N A369285 Number of connected binary matrices with n ones, no zero rows or columns, and distinct rows and columns.
%H A369285 Andrew Howroyd, <a href="/A369285/b369285.txt">Table of n, a(n) for n = 0..40</a>
%e A369285 The a(3) = 4 matrices:
%e A369285 [1 1] [1 1] [1 0] [0 1]
%e A369285 [1 0] [0 1] [1 1] [1 1]
%o A369285 (PARI) \\ Q, ConnectedMats defined in A321588.
%o A369285 seq(n)={my(R=vectorv(n,m,Q(m,n,w->1 + y^w + O(y*y^n)))); for(i=2, #R, R[i] -= i*R[i-1]); Vec(1 + vecsum(vecsum(Vec(ConnectedMats(Mat(R))))))}
%Y A369285 Cf. A321446, A321515, A321588.
%K A369285 nonn
%O A369285 0,4
%A A369285 _Andrew Howroyd_, Jan 24 2024