A374168 a(n) is the smallest number which can be represented as the sum of two nonzero square pyramidal numbers in exactly n ways, or -1 if no such number exists.
2, 60, 9692375
Offset: 1
Examples
a(2) = 60 = 5 + 55 = 30 + 30.
Links
- Eric Weisstein's World of Mathematics, Square Pyramidal Number.
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