A171032 -id:A171032 - cp's OEIS frontend

A180547 Primes that become a different prime under the mapping 4 <=> 6.

41, 47, 61, 67, 347, 367, 401, 419, 431, 461, 463, 467, 491, 601, 619, 631, 641, 643, 647, 691, 947, 967, 1049, 1069, 1409, 1427, 1447, 1493, 1499, 1609, 1627, 1667, 1693, 1699, 1847, 1867, 2141, 2161, 2417, 2459, 2467, 2477, 2617, 2647, 2659, 2677, 3041

Offset: 1

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

Harvey P. Dale, Table of n, a(n) for n = 1..1000
Index to Primes, Primes that become a different prime under some mapping.

Cf. A171032, A175791, A180517 thru A180559, A175789, A180560, A180561.

fQ[n_] := Block[{id = IntegerDigits@n}, (MemberQ[id, 4] || MemberQ[id, 6]) && PrimeQ[ FromDigits[ id /. {4 -> 6, 6 -> 4}] ]]; Select[ Prime@ Range@ 440, fQ]
dpQ[n_]:=(DigitCount[n,10,4]>0 || DigitCount[n,10,6]>0)&&PrimeQ[ FromDigits[ IntegerDigits[n]/.{4->a,6->b}/.{a->6,b->4}]]; Select[ Prime[ Range[500]],dpQ](* Harvey P. Dale, Feb 28 2022 *)

A222241 In the number n, replace all (decimal) digits '4' with '6' and vice versa.

Original entry on oeis.org

0, 1, 2, 3, 6, 5, 4, 7, 8, 9, 10, 11, 12, 13, 16, 15, 14, 17, 18, 19, 20, 21, 22, 23, 26, 25, 24, 27, 28, 29, 30, 31, 32, 33, 36, 35, 34, 37, 38, 39, 60, 61, 62, 63, 66, 65, 64, 67, 68, 69, 50, 51, 52, 53, 56, 55, 54, 57, 58, 59, 40, 41, 42, 43, 46, 45, 44, 47, 48, 49, 70, 71, 72, 73, 76, 75

Offset: 0

M. F. Hasler, Feb 13 2013

The map which is applied to primes in A171032.

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

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

a[n_]:= IntegerDigits[n]/.{4->6, 6->4} // FromDigits; Table[a[n], {n, 0, 80}] (* Vincenzo Librandi, Jul 31 2013 *)

A222241(n,d=[0, 1, 2, 3, 6, 5, 4, 7, 8, 9])={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

A180547 Primes that become a different prime under the mapping 4 <=> 6.

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