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 A374193 #15 Feb 16 2025 08:34:07 %S A374193 2,1471,269406 %N A374193 a(n) is the smallest number which can be represented as the sum of two nonzero pentagonal pyramidal numbers in exactly n ways, or -1 if no such number exists. %C A374193 There are no further positive terms <= 10^15. - _Michael S. Branicky_, Jul 01 2024 %H A374193 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PentagonalPyramidalNumber.html">Pentagonal Pyramidal Number</a> %e A374193 a(2) = 1471 = 1 + 1470 = 288 + 1183. %Y A374193 Cf. A002411, A011541, A332989, A334013, A374168, A374194. %K A374193 nonn,hard,more,bref %O A374193 1,1 %A A374193 _Ilya Gutkovskiy_, Jun 30 2024