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 A374807 #5 Feb 16 2025 08:34:07 %S A374807 20,38,47,64,73,92,97,110,127,115,130,164,185,172,208,157,199,235,247, %T A374807 232,220,272,277,304,280,361,262,307,319,391,322,292,495,415,337,367, %U A374807 370,382,478,482,412,409,445,430,467,500,427,532,493 %N A374807 a(n) is the smallest number which can be represented as the sum of 4 distinct nonzero triangular numbers in exactly n ways, or -1 if no such number exists. %H A374807 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TriangularNumber.html">Triangular Number</a> %e A374807 a(3) = 47 = 1 + 3 + 15 + 28 = 1 + 10 + 15 + 21 = 3 + 6 + 10 + 28. %Y A374807 Cf. A000217, A025417, A342326, A374806. %K A374807 nonn %O A374807 1,1 %A A374807 _Ilya Gutkovskiy_, Jul 20 2024