A171056 -id:A171056 - cp's OEIS frontend

A180559 Primes that become a different prime under the mapping 7 <=> 9.

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

Offset: 1

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

John Cerkan, Table of n, a(n) for n = 1..10000
Index to Primes, Primes that become a different prime under some mapping.

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

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

A222253 In the number n, replace all (decimal) digits '7' with '9' and vice versa.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 9, 8, 7, 10, 11, 12, 13, 14, 15, 16, 19, 18, 17, 20, 21, 22, 23, 24, 25, 26, 29, 28, 27, 30, 31, 32, 33, 34, 35, 36, 39, 38, 37, 40, 41, 42, 43, 44, 45, 46, 49, 48, 47, 50, 51, 52, 53, 54, 55, 56, 59, 58, 57, 60, 61, 62, 63, 64, 65, 66, 69, 68, 67, 90, 91, 92, 93, 94, 95

Offset: 0

M. F. Hasler, Feb 13 2013

The map which is applied to primes in A171056.

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Cf. A222210-A222254; A171013-A171016, A175770, A171018-A171057.

a[n_]:= IntegerDigits[n]/.{7->9, 9->7}//FromDigits; Table[a[n], {n, 0, 80}] (* Vincenzo Librandi, Jul 29 2013 *)

A222253(n,d=[0, 1, 2, 3, 4, 5, 6, 9, 8, 7])=sum(i=1,#n=digits(n),d[n[i]+1]*10^(#n-i),!n*d[1]) \\ N.B.: digits(0)=[] in PARI (v.2.6)

cp's OEIS Frontend

A180559 Primes that become a different prime under the mapping 7 <=> 9.

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