cp's OEIS Frontend

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.

A368074 a(n) is the least number k such that the k-th n-gonal number can be written as the difference of two positive n-gonal numbers in exactly n ways.

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%I A368074 #6 Feb 16 2025 08:34:06
%S A368074 5,12,82,105,297,182
%N A368074 a(n) is the least number k such that the k-th n-gonal number can be written as the difference of two positive n-gonal numbers in exactly n ways.
%C A368074 The corresponding n-gonal numbers are in A368075.
%H A368074 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PolygonalNumber.html">Polygonal Number</a>
%e A368074 a(3) = 5: T(5) = T(6) - T(3) = T(8) - T(6) = T(15) - T(14), where T(k) is the k-th triangular number.
%Y A368074 Cf. A086270, A338105, A368041, A368075.
%K A368074 nonn,more
%O A368074 3,1
%A A368074 _Ilya Gutkovskiy_, Dec 10 2023