A171053 -id:A171053 - cp's OEIS frontend

A180550 Primes that become a different prime under the mapping 4 <=> 9.

47, 97, 347, 397, 467, 491, 641, 691, 941, 967, 1433, 1447, 1451, 1487, 1933, 1951, 1987, 1997, 2243, 2293, 2417, 2543, 2593, 2741, 2791, 2917, 3407, 3467, 3907, 3967, 4001, 4007, 4013, 4091, 4093, 4127, 4133, 4157, 4243, 4283, 4337, 4391, 4423, 4597

Offset: 1

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

Robert Price, Table of n, a(n) for n = 1..1559
Index to Primes, Primes that become a different prime under some mapping.

Cf. A171053, A175791, A180517 thru A180559, A175789, A180560, A180561.

fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 4] || MemberQ[id, 9]) && PrimeQ[ FromDigits[ id /. {4 -> 9, 9 -> 4}] ]]; Select[ Prime@ Range@ 650, fQ]

A222244 In the number n, replace all (decimal) digits '4' with '9' and vice versa.

Original entry on oeis.org

0, 1, 2, 3, 9, 5, 6, 7, 8, 4, 10, 11, 12, 13, 19, 15, 16, 17, 18, 14, 20, 21, 22, 23, 29, 25, 26, 27, 28, 24, 30, 31, 32, 33, 39, 35, 36, 37, 38, 34, 90, 91, 92, 93, 99, 95, 96, 97, 98, 94, 50, 51, 52, 53, 59, 55, 56, 57, 58, 54, 60, 61, 62, 63, 69, 65, 66, 67, 68, 64, 70, 71, 72, 73, 79, 75

Offset: 0

M. F. Hasler, Feb 13 2013

The map which is applied to primes in A171053.

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

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

a[n_]:= IntegerDigits[n]/.{4->9, 9->4} // FromDigits; Table[a[n], {n, 0, 80}] (* Vincenzo Librandi, Jul 31 2013 *)

A222244(n,d=[0, 1, 2, 3, 9, 5, 6, 7, 8, 4])={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

A180550 Primes that become a different prime under the mapping 4 <=> 9.

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