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 A331251 #7 Jan 19 2020 20:40:30 %S A331251 1,1,1,2,1,2,1,2,2,1,1,2,2,3,1,3,3,1,2,2,1,3,1,2,3,2,1,3,2,1,3,4,2,4, %T A331251 1,3,2,3,1,3,4,2,4,1,2,4,1,3,3,2,3,1,2,4,1,4,4,5,2,3,4,2,1,3,3,1,2,5, %U A331251 4,2,1,3,4,5,1,4,2,3,3,2,4,1,5,5,3,4,1,5 %N A331251 Triangles with integer sides i <= j <= k sorted by area, and, in case of ties, lexicographically by side lengths (smallest first). The sequence gives shortest side i. The other sides are in A331252 and A331253. %e A331251 List of first triangles: %e A331251 n %e A331251 | 16*A^2 %e A331251 | | i .... (this sequence) %e A331251 | | | j .. (A331252) %e A331251 | | | | k (A331253) %e A331251 | | | | | %e A331251 1 3 1 1 1 %e A331251 2 15 1 2 2 %e A331251 3 35 1 3 3 %e A331251 4 48 2 2 2 %e A331251 5 63 1 4 4 %e A331251 6 63 2 2 3 %e A331251 7 99 1 5 5 %e A331251 8 128 2 3 3 %e A331251 9 135 2 3 4 %e A331251 10 143 1 6 6 %e A331251 11 195 1 7 7 %Y A331251 Cf. A316841, A316843, A316844, A316845, A316853, A317182, A331011. %Y A331251 Cf. A331252 (middle side j), A331253 (longest side k). %K A331251 nonn %O A331251 1,4 %A A331251 _Hugo Pfoertner_, Jan 19 2020