cp's OEIS Frontend

A374579 a(n) is the smallest number which can be represented as the sum of n distinct nonzero fourth powers in exactly 2 ways, or -1 if no such number exists.

%I A374579 #9 Jul 16 2024 16:14:50
%S A374579 -1,635318657,6578,6834,7459,8755,18755,23412,43893,53893,92309,
%T A374579 123335,182566,232647,298183,393848,521849,681849,872105,1066586,
%U A374579 1343612,1623453,1955229,2412205,2811596,3424941,4132222
%N A374579 a(n) is the smallest number which can be represented as the sum of n distinct nonzero fourth powers in exactly 2 ways, or -1 if no such number exists.
%e A374579 a(2) = 635318657 = 59^4 + 158^4 = 133^4 + 134^4.
%e A374579 a(3) = 6578 = 1^4 + 2^4 + 9^4 = 3^4 + 7^4 + 8^4.
%Y A374579 Cf. A000538, A003824, A360306, A374287, A374417.
%K A374579 sign,more
%O A374579 1,2
%A A374579 _Ilya Gutkovskiy_, Jul 12 2024
%E A374579 a(18)-a(27) from _Michael S. Branicky_, Jul 13 2024