Search: a374230 -id:a374230
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A374229
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a(n) is the smallest number which can be represented as the sum of three distinct n-th powers of primes in exactly n ways, or -1 if no such number exists.
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+10
2
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(2) = 414 = 2^2 + 7^2 + 19^2 = 2^2 + 11^2 + 17^2.
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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STATUS
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approved
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A374272
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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.
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+10
2
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OFFSET
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1,2
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LINKS
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EXAMPLE
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a(2) = 10370 = 13^2 + 101^2 = 31^2 + 97^2 = 59^2 + 83^2 = 71^2 + 73^2.
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.
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CROSSREFS
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KEYWORD
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sign,more
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AUTHOR
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STATUS
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approved
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