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%I #4 Dec 31 2022 15:25:39
%S 2300,6201,8125,6391
%N a(n) is the smallest n-gonal pyramidal number which can be represented as the sum of n distinct nonzero n-gonal pyramidal numbers in exactly n ways, or -1 if none exists.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PyramidalNumber.html">Pyramidal Number</a>
%e For n = 3: 2300 = 1 + 969 + 1330 = 56 + 220 + 2024 = 165 + 364 + 1771.
%e For n = 4: 6201 = 1 + 91 + 1785 + 4324 = 1 + 285 + 1015 + 4900 = 30 + 140 + 506 + 5525 = 91 + 819 + 1496 + 3795.
%Y Cf. A080851, A350210, A350397, A350423.
%K nonn,more
%O 3,1
%A _Ilya Gutkovskiy_, Dec 25 2022
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