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%I #4 Jul 07 2024 21:05:45
%S -1,10370,999979163,199898912404
%N a(n) is the smallest number which can be represented as the sum of n distinct n-th powers of primes in exactly 4 ways, or -1 if no such number exists.
%e a(2) = 10370 = 13^2 + 101^2 = 31^2 + 97^2 = 59^2 + 83^2 = 71^2 + 73^2.
%e a(3) = 999979163 = 83^3 + 757^3 + 827^3 = 107^3 + 677^3 + 883^3 = 197^3 + 523^3 + 947^3 = 281^3 + 419^3 + 967^3.
%Y Cf. A349764, A374230, A374269, A374270, A374271.
%K sign,more
%O 1,2
%A _Ilya Gutkovskiy_, Jul 02 2024