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A171018 In the sequence of prime numbers, replace all the '3' digits with '2' and vice versa. 46

%I

%S 3,2,5,7,11,12,17,19,32,39,21,27,41,42,47,52,59,61,67,71,72,79,82,89,

%T 97,101,102,107,109,112,137,121,127,129,149,151,157,162,167,172,179,

%U 181,191,192,197,199,311,332,337,339,322,329,341,351,357,362

%N In the sequence of prime numbers, replace all the '3' digits with '2' and vice versa.

%H Vincenzo Librandi, <a href="/A171018/b171018.txt">Table of n, a(n) for n = 1..1000</a>

%t f[n_]:=FromDigits[(IntegerDigits[n]/.{2->a,3->b}) /.{a->3,b->2}]; f/@Prime[Range[80]] (* _Harvey P. Dale_, Apr 01 2011 *)

%o (PARI) a(n)=my(v=[0,1,3,2,4,5,6,7,8,9]);apply(k->v[k+1],digits(prime(n))) \\ _Charles R Greathouse IV_, Jul 16 2013

%K nonn,base,easy

%O 1,1

%A _N. J. A. Sloane_ and _Vincenzo Librandi_, Sep 04 2010

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Last modified August 10 12:39 EDT 2020. Contains 336379 sequences. (Running on oeis4.)