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%I #14 Jul 01 2024 13:11:49
%S 2,1471,269406
%N 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 There are no further positive terms <= 10^15. - _Michael S. Branicky_, Jul 01 2024
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PentagonalPyramidalNumber.html">Pentagonal Pyramidal Number</a>
%e a(2) = 1471 = 1 + 1470 = 288 + 1183.
%Y Cf. A002411, A011541, A332989, A334013, A374168, A374194.
%K nonn,hard,more,bref
%O 1,1
%A _Ilya Gutkovskiy_, Jun 30 2024