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A098466
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Numbers k such that N*2^k - 1 is prime where N = 9999999999999999999999988888888888888888887777777777777777766666666666665555555555544444443333322211.
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1
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OFFSET
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1,1
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COMMENTS
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9999999999999999999999988888888888888888887777777777777777766666666666665555555555544444443333322211 is a 100-digit prime that is easy to remember: 23 9's then 19 8's then 17 7's then 13 6's then 11 5's then 7 4's then 5 3's then 3 2's and 2 1's. Writing p(k) for prime(k), this is p(9)9 p(8)8 p(7)7 p(6)6 p(5)5 p(4)4 p(3)3 p(2)2 p(1)1.
Same number can be shortened as (10^100-(10^77+10^58+10^41+10^28+10^17+10^10+10^5-7)/9-12). (By David A. Corneth, original comment can be found in A098467)
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LINKS
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CROSSREFS
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KEYWORD
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nonn,more,less
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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