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A180537
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Primes that become a different prime under the mapping 2 <=> 7.
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0
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2, 7, 23, 29, 73, 79, 223, 233, 239, 251, 269, 521, 571, 733, 739, 751, 769, 773, 1259, 1283, 1289, 1759, 1783, 1789, 1823, 1873, 2029, 2039, 2069, 2179, 2203, 2273, 2293, 2309, 2333, 2351, 2371, 2393, 2411, 2459, 2549, 2579, 2591, 2671, 2699, 2711, 2713
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..47.
Index to Primes, Primes that become a different prime under some mapping.
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MATHEMATICA
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fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 2] || MemberQ[id, 7]) && PrimeQ[ FromDigits[ id /. {2 -> 7, 7 -> 2}] ]]; Select[ Prime@ Range@ 400, fQ]
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CROSSREFS
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Cf. A171036, A175791, A180517 thru A180559, A175789, A180560, A180561.
Sequence in context: A122631 A147969 A045381 * A042145 A186098 A040098
Adjacent sequences: A180534 A180535 A180536 * A180538 A180539 A180540
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KEYWORD
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base,nonn
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AUTHOR
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Zak Seidov and Robert G. Wilson v, Sep 09 2010
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STATUS
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approved
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