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A081981
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Primes p such that p+1 is divisible by every nonzero digit of p.
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6
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11, 23, 101, 113, 131, 167, 211, 233, 263, 269, 311, 359, 383, 431, 443, 727, 863, 1013, 1021, 1031, 1061, 1103, 1163, 1201, 1217, 1223, 1259, 1301, 1361, 1427, 1439, 1601, 1613, 1619, 1637, 1721, 1777, 1823, 1847, 2003, 2011, 2063, 2069, 2111, 2213, 2221
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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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a(n) = 576n log n + O(n^0.955), since primes = 2519 mod 2520 are all in this sequence, and almost all (in the sense of natural density) terms of this sequence are of that form. - Charles R Greathouse IV, Sep 06 2022
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EXAMPLE
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167 is a member as 168 is divisible by 1, 6 and 7.
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PROG
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(Python)
from sympy import isprime
def ok(n): return all((n+1)%int(d) == 0 for d in set(str(n)) - {"0"}) and isprime(n)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 06 2003
Added "nonzero" to definition following a comment by Harvey Dale. - N. J. A. Sloane, Jan 08 2011.
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STATUS
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approved
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