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A125504
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Smallest number k such that the numerator of alternating generalized harmonic number H'(k,n) = Sum[ (-1)^(i+1) * 1/i^n, {i,1,k} ] is a prime.
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0
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3, 2, 2, 3, 2, 19, 2, 146, 87, 3, 16, 3, 2, 249, 15, 87, 2, 699, 2
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OFFSET
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1,1
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COMMENTS
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a(n) = 3 for n in {1,4,10,12,24,27,39,...}.
a(n) = 5 for n in {26,76,132,205,238,...}.
a(n) = 9 for n in {100,200,...}.
a(n) = 15 for n in {15,33,65,...}.
a(21) = 18. a(22) = 13. a(41) = 6. a(72) = 11. a(173) = 8.
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LINKS
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CROSSREFS
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KEYWORD
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hard,more,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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