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A097743
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Numbers of the form 3*2^(p - 1) - 1 where p is prime.
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8
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5, 11, 47, 191, 3071, 12287, 196607, 786431, 12582911, 805306367, 3221225471, 206158430207, 3298534883327, 13194139533311, 211106232532991, 13510798882111487, 864691128455135231, 3458764513820540927
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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p=2, 2^(2-1) + (2^2 - 1) = 5;
p=3, 2^(3-1) + (2^3 - 1) = 11.
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MATHEMATICA
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PROG
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(PARI) a(n) = 3*2^(prime(n) - 1) - 1; \\ Michel Marcus, Nov 30 2017
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CROSSREFS
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KEYWORD
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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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