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A098919
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Least k such that k*M#(n) - 1 is prime where M#(n) is the product of the first n Mersenne primes.
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0
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2, 2, 2, 16, 2, 24, 8, 66, 6, 38, 44, 142, 116, 20, 460, 2974, 5774, 1110, 2520, 3422
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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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2*(2^2-1)*(2^3-1)*(2^5-1) - 1 = 1301, which is prime, so k(3)=2.
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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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