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 A334007 #13 Feb 16 2025 08:34:00 %S A334007 1,10,2180,10053736,13291443468940 %N A334007 a(n) is the least integer that can be expressed as the sum of one or more consecutive nonzero triangular numbers in exactly n ways. %H A334007 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/TriangularNumber.html">Triangular Number</a> %H A334007 <a href="/index/Pol#polygonal_numbers">Index to sequences related to polygonal numbers</a> %e A334007 Let S(k, m) denote the sum of m triangular numbers starting from k(k+1)/2. We have %e A334007 a(1) = S(1, 1); %e A334007 a(2) = S(4, 1) = S(1, 3); %e A334007 a(3) = S(31, 4) = S(27, 5) = S(9, 15); %e A334007 a(4) = S(945, 22) = S(571, 56) = S(968, 21) = S(131, 266); %e A334007 a(5) = S(4109, 38947) = S(25213, 20540) = S(10296, 32943) = S(32801, 15834) = S(31654, 16472). %Y A334007 Cf. A000217, A054859, A068314, A034706, A050943, A186337, A298467, A307666, A309783, A334008, A334010, A334011, A334012. %K A334007 nonn,hard,more %O A334007 1,2 %A A334007 _Ilya Gutkovskiy_, Apr 12 2020 %E A334007 a(5) from _Giovanni Resta_, Apr 13 2020