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A180559 Primes that become a different prime under the mapping 7 <=> 9. 46
17, 19, 79, 97, 107, 109, 137, 139, 173, 179, 193, 197, 227, 229, 347, 349, 379, 397, 577, 599, 617, 619, 709, 727, 739, 769, 827, 829, 857, 859, 907, 929, 937, 967, 1279, 1297, 1427, 1429, 1487, 1489, 1579, 1597, 1607, 1609, 1667, 1669, 1709, 1733, 1747 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..49.

Index to Primes, Primes that become a different prime under some mapping.

MATHEMATICA

fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 7] || MemberQ[id, 9]) && PrimeQ[ FromDigits[ id /. {7 -> 9, 9 -> 7}] ]]; Select[ Prime@ Range@ 275, fQ]

CROSSREFS

Cf. A171056, A175791, A180517 thru A180559, A175789, A180560, A180561.

Sequence in context: A232878 A226681 A005808 * A028489 A210242 A165320

Adjacent sequences:  A180556 A180557 A180558 * A180560 A180561 A180562

KEYWORD

base,nonn

AUTHOR

Zak Seidov and Robert G. Wilson v, Sep 09 2010

STATUS

approved

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Last modified April 21 06:23 EDT 2014. Contains 240824 sequences.