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 A331715 #6 Jan 31 2020 20:14:24
%S A331715 1,11,66,278,966,2957,8149,20676,48911,108942,230201,464528,899633,
%T A331715 1679685,3034620
%N A331715 Number of non-isomorphic set-systems with 4 sets each with n elements.
%C A331715 a(n) is the number of nonequivalent binary matrices with 4 distinct columns and any number of nonzero rows with n ones in every column up to permutation of rows and columns.
%e A331715 The a(2) = 11 matrices are:
%e A331715 [1 0 0 0] [1 1 0 0] [1 1 1 0] [1 1 0 0] [1 1 0 0]
%e A331715 [1 0 0 0] [1 0 0 0] [1 0 0 0] [1 0 1 0] [1 0 0 0]
%e A331715 [0 1 0 0] [0 1 0 0] [0 1 0 0] [0 1 0 0] [0 1 0 0]
%e A331715 [0 1 0 0] [0 0 1 0] [0 0 1 0] [0 0 1 0] [0 0 1 1]
%e A331715 [0 0 1 0] [0 0 1 0] [0 0 0 1] [0 0 0 1] [0 0 1 0]
%e A331715 [0 0 1 0] [0 0 0 1] [0 0 0 1] [0 0 0 1] [0 0 0 1]
%e A331715 [0 0 0 1] [0 0 0 1]
%e A331715 [0 0 0 1]
%e A331715 .
%e A331715 [1 1 1 1] [1 1 1 0] [1 1 0 0] [1 1 0 0] [1 1 0 1] [1 1 0 0]
%e A331715 [1 0 0 0] [1 0 0 1] [1 0 1 0] [1 0 1 0] [1 0 1 0] [1 0 1 0]
%e A331715 [0 1 0 0] [0 1 0 0] [0 1 1 0] [0 1 0 1] [0 1 1 0] [0 1 0 1]
%e A331715 [0 0 1 0] [0 0 1 0] [0 0 0 1] [0 0 1 0] [0 0 0 1] [0 0 1 1]
%e A331715 [0 0 0 1] [0 0 0 1] [0 0 0 1] [0 0 0 1]
%e A331715 .
%e A331715 A set system corresponding to the first of these is {{1,2}, {3,4}, {5,6}, {7,8}}.
%Y A331715 Column k=4 of A331508.
%Y A331715 Cf. A331714.
%K A331715 nonn,more
%O A331715 1,2
%A A331715 _Andrew Howroyd_, Jan 31 2020