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A225578
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Sum of first (prime(n) - 1) (prime(n) - 1)th powers.
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2
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1, 5, 354, 67171, 14914341925, 13421957361110, 28101527071305611528, 60182438244917445266889, 525344775209112229247070397995, 51296981152155330485450049059398345004638, 319099356359853147544285512855368258519442575
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OFFSET
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1,2
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COMMENTS
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It follows from Fermat's little theorem that a(n) is congruent to -1 mod the n-th prime.
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REFERENCES
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Paulo Ribemboim, The Little Book of Big Primes, New York, Springer-Verlag (1991): 17.
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LINKS
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FORMULA
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a(n) = sum(i = 1 .. prime(n) - 1, i^(prime(n) - 1)).
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EXAMPLE
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a(2) = 5 because, since 3 is the second prime, we have 1^2 + 2^2 = 1 + 4 = 5.
a(3) = 354 because, since 5 is the third prime, we have 1^4 + 2^4 + 3^4 + 4^4 = 1 + 4 + 81 + 256 = 354.
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MATHEMATICA
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Table[Sum[i^(Prime[n] - 1), {i, Prime[n] - 1}], {n, 15}]
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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