A171048 -id:A171048 - cp's OEIS frontend

A180558 Primes that become a different prime under the mapping 7 <=> 8.

73, 79, 83, 89, 271, 281, 373, 379, 383, 389, 673, 683, 709, 739, 773, 809, 839, 883, 1171, 1181, 1279, 1289, 1471, 1481, 1723, 1783, 1789, 1823, 1873, 1879, 2371, 2381, 2719, 2789, 2819, 2879, 3079, 3089, 3571, 3581, 3733, 3779, 3833, 3889, 4273, 4283

Offset: 1

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

Robert Price, Table of n, a(n) for n = 1..1582
Index to Primes, Primes that become a different prime under some mapping.

Cf. A171048, A175791, A180517 thru A180559, A175789, A180560, A180561.

fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 7] || MemberQ[id, 8]) && PrimeQ[ FromDigits[ id /. {7 -> 8, 8 -> 7}] ]]; Select[ Prime@ Range@ 600, fQ]

A222252 In the number n, replace all (decimal) digits '7' with '8' and vice versa.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 8, 7, 9, 10, 11, 12, 13, 14, 15, 16, 18, 17, 19, 20, 21, 22, 23, 24, 25, 26, 28, 27, 29, 30, 31, 32, 33, 34, 35, 36, 38, 37, 39, 40, 41, 42, 43, 44, 45, 46, 48, 47, 49, 50, 51, 52, 53, 54, 55, 56, 58, 57, 59, 60, 61, 62, 63, 64, 65, 66, 68, 67, 69, 80, 81, 82, 83, 84, 85

Offset: 0

M. F. Hasler, Feb 13 2013

The map which is applied to primes in A171048.

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

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

a[n_]:= IntegerDigits[n]/.{7->8,8->7} // FromDigits; Table[a[n], {n, 0, 80}] (* Vincenzo Librandi, Jul 29 2013 *)

A222252(n,d=[0, 1, 2, 3, 4, 5, 6, 8, 7, 9])=sum(i=1, #n=digits(n), d[n[i]+1]*10^(#n-i)) \\ gives correct value for n=0 iff d[1]=0, since digits(0)=[] in PARI (v.2.6)

Corrected term by Vincenzo Librandi, Jul 29 2013

cp's OEIS Frontend

A180558 Primes that become a different prime under the mapping 7 <=> 8.

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