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A171027 In the sequence of prime numbers, replace all the '5' digits with '4' and vice versa. 3

%I

%S 2,3,4,7,11,13,17,19,23,29,31,37,51,53,57,43,49,61,67,71,73,79,83,89,

%T 97,101,103,107,109,113,127,131,137,139,159,141,147,163,167,173,179,

%U 181,191,193,197,199,211,223,227,229,233,239,251,241,247,263

%N In the sequence of prime numbers, replace all the '5' digits with '4' and vice versa.

%H Vincenzo Librandi, <a href="/A171027/b171027.txt">Table of n, a(n) for n = 1..1000</a>

%t FromDigits[IntegerDigits[#]/.{5->p, 4->q}/.{p->4, q->5}]&/@Prime[Range[100]] (* _Vincenzo Librandi_, Apr 07 2013 *)

%o (PARI) a(n)=my(v=[0,1,2,3,5,4,6,7,8,9]);subst(Pol(apply(k->v[k+1], digits(prime(n)))),'x,10) \\ _Charles R Greathouse IV_, Jul 24 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 January 19 18:36 EST 2022. Contains 350466 sequences. (Running on oeis4.)