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.

A374194 a(n) is the smallest number which can be represented as the sum of two nonzero hexagonal pyramidal numbers in exactly n ways, or -1 if no such number exists.

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%I A374194 #15 Feb 16 2025 08:34:07
%S A374194 2,5972,5170425
%N A374194 a(n) is the smallest number which can be represented as the sum of two nonzero hexagonal pyramidal numbers in exactly n ways, or -1 if no such number exists.
%C A374194 There are no further positive terms <= 10^15. - _Michael S. Branicky_, Jun 30 2024
%H A374194 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HexagonalPyramidalNumber.html">Hexagonal Pyramidal Number</a>
%e A374194 a(2) = 5972 = 1222 + 4750 = 1925 + 4047.
%Y A374194 Cf. A002412, A011541, A334013, A374141, A374168, A374193.
%K A374194 nonn,hard,more,bref
%O A374194 1,1
%A A374194 _Ilya Gutkovskiy_, Jun 30 2024