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%I #5 Aug 12 2024 13:11:33
%S -1,187,2492,56290,24993485,2063792939
%N a(n) is the smallest number which can be represented as the sum of 6 distinct positive n-th powers in exactly 4 ways, or -1 if no such number exists.
%e a(6) = 2063792939 = 1^6 + 4^6 + 16^6 + 21^6 + 31^6 + 32^6
%e = 4^6 + 7^6 + 20^6 + 22^6 + 29^6 + 33^6
%e = 5^6 + 7^6 + 16^6 + 25^6 + 30^6 + 32^6
%e = 5^6 + 8^6 + 14^6 + 27^6 + 29^6 + 32^6.
%Y Cf. A046881, A342900, A374418, A374421, A374422, A374423, A374424, A374425, A375329, A375330, A375331, A375332, A375334.
%K sign,hard,more
%O 1,2
%A _Ilya Gutkovskiy_, Aug 12 2024