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In the number n, replace all (decimal) digits '1' with '7' and vice versa.
1

%I #10 Mar 31 2017 00:25:03

%S 0,7,2,3,4,5,6,1,8,9,70,77,72,73,74,75,76,71,78,79,20,27,22,23,24,25,

%T 26,21,28,29,30,37,32,33,34,35,36,31,38,39,40,47,42,43,44,45,46,41,48,

%U 49,50,57,52,53,54,55,56,51,58,59,60,67,62,63,64,65,66,61,68,69,10,17,12,13,14,15

%N In the number n, replace all (decimal) digits '1' with '7' and vice versa.

%C The map which is applied to primes in A171035.

%H Vincenzo Librandi, <a href="/A222224/b222224.txt">Table of n, a(n) for n = 0..1000</a>

%t a[n_]:= IntegerDigits[n]/.{1->7, 7->1} // FromDigits; Table[a[n], {n, 0, 80}] (* _Vincenzo Librandi_, Jul 29 2013 *)

%o (PARI) A222224(n,d=[0,7,2,3,4,5,6,1,8,9])=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)

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

%K nonn,base,easy

%O 0,2

%A _M. F. Hasler_, Feb 12 2013