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 A278321 #4 Nov 18 2016 06:40:54 %S A278321 1,94,1678,19854,186987,1548002,11947350,87562135,605431820, %T A278321 3905165468,23355599964,129475795828,667503759881,3215875683718, %U A278321 14555156486463,62204964640341,252211338710097,974245904884957,3598868691539578 %N A278321 Number of nX4 0..1 arrays with rows and columns in lexicographic nondecreasing order but with exactly two mistakes. %C A278321 Column 4 of A278325. %H A278321 R. H. Hardin, <a href="/A278321/b278321.txt">Table of n, a(n) for n = 1..210</a> %F A278321 Empirical polynomial of degree 47 (see link above) %e A278321 Some solutions for n=4 %e A278321 ..0..1..1..0. .1..1..0..0. .0..1..0..1. .0..1..0..1. .1..1..0..1 %e A278321 ..1..0..1..1. .0..0..0..0. .0..1..1..1. .0..1..0..1. .1..1..0..1 %e A278321 ..0..1..0..0. .1..1..1..1. .1..1..1..0. .0..0..0..0. .1..1..0..1 %e A278321 ..1..1..0..1. .1..1..1..1. .0..1..1..1. .0..0..0..0. .0..0..1..1 %Y A278321 Cf. A278325. %K A278321 nonn %O A278321 1,2 %A A278321 _R. H. Hardin_, Nov 18 2016