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A091631
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Next prime associated with A091628.
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5
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29, 227, 2237, 22229, 222247, 2222239, 22222253, 222222227, 2222222243, 22222222273, 222222222301, 2222222222243, 22222222222229, 222222222222227, 2222222222222281, 22222222222222301, 222222222222222281
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OFFSET
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1,1
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COMMENTS
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Sequence arising in Farideh Firoozbakht's solution to Prime Puzzle 251 - 23 is the only pointer prime (A089823) not containing the digit "1".
The monotonically increasing value of successive product of digits (A091629) strongly suggests that in successive n the digit 1 must be present.
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LINKS
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FORMULA
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EXAMPLE
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a(1) = nextprime(23+1) = 29.
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PROG
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(PARI) a(n) = nextprime((10^(n+1) - 1)/9*2 + 2); \\ Michel Marcus, Mar 18 2018
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CROSSREFS
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KEYWORD
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base,easy,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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