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A360218 a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero square pyramidal numbers in exactly n ways, or -1 if no such integer exists.

%I A360218 #14 Feb 16 2025 08:34:04
%S A360218 1,5580,2814,1980,1595,1700,2175,2415,2830,3740,4810,5995,7610,9240,
%T A360218 11380,13896,16506,19735,23150,27441,32085,36721,42755,49570,56610,
%U A360218 65135,73165,83021,93835,105671,118255,132545,147546,163516,182155,201040,222371,244280,267856
%N A360218 a(n) is the smallest positive integer which can be represented as the sum of n distinct nonzero square pyramidal numbers in exactly n ways, or -1 if no such integer exists.
%H A360218 Michael S. Branicky, <a href="/A360218/b360218.txt">Table of n, a(n) for n = 1..80</a>
%H A360218 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SquarePyramidalNumber.html">Square Pyramidal Number</a>
%e A360218 For n = 3: 2814 = 14 + 1015 + 1785 = 55 + 650 + 2109 = 140 + 204 + 2470.
%Y A360218 Cf. A000330, A350206, A350241, A350397, A360217.
%K A360218 nonn
%O A360218 1,2
%A A360218 _Ilya Gutkovskiy_, Jan 30 2023
%E A360218 a(18)-a(33) from _Michael S. Branicky_, Feb 04 2023
%E A360218 a(34) and beyond from _Michael S. Branicky_, Feb 18 2023