A035043 Replace any decimal digit '1' with '2' and vice versa.

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

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• base
• easy

Comments

The map which is applied to primes in A171015. - M. F. Hasler, Feb 12 2013

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]/.{1->2, 2->1} // FromDigits; Table[a[n], {n, 0, 80}] (* Vincenzo Librandi, Jul 29 2013 *)

PARI

A035043(n, d=[0, 2, 1, 3, 4, 5, 6, 7, 8, 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) M. F. Hasler, Feb 12 2013

Extensions

Definition rephrased by M. F. Hasler, Oct 26 2013