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

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

Author

M. F. Hasler, Feb 13 2013

Keywords

• nonn
• base
• easy

Comments

The map which is applied to primes in A171048.

Links

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

Crossrefs

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

Programs

Mathematica

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

PARI

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)

Extensions

Corrected term by Vincenzo Librandi, Jul 29 2013