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 A057876 Primes p with the following property: let d_1, d_2, ... be the distinct digits occurring in the decimal expansion of p. Then for each d_i, dropping all the digits d_i from p produces a prime number.  Leading 0's are not allowed. 10

%I

%S 23,37,53,73,113,131,137,151,173,179,197,211,311,317,431,617,719,1531,

%T 1831,1997,2113,2131,2237,2273,2297,2311,2797,3137,3371,4337,4373,

%U 4733,4919,6173,7297,7331,7573,7873,8191,8311,8831,8837,12239,16673,19531

%N Primes p with the following property: let d_1, d_2, ... be the distinct digits occurring in the decimal expansion of p. Then for each d_i, dropping all the digits d_i from p produces a prime number. Leading 0's are not allowed.

%H Robert Israel, <a href="/A057876/b057876.txt">Table of n, a(n) for n = 1..1000</a>

%e 1531 gives primes 53, 131 and 151 after dropping digits 1, 5 and 3.

%e A larger example 1210778071 gives primes 12177871, 2077807, 110778071, 1210801 and 121077071 after dropping digits 0, 1, 2, 7 and 8.

%p filter:= proc(n) local L,d,Lp;

%p if not isprime(n) then return false fi;

%p L:= convert(n,base,10);

%p for d in convert(L,set) do

%p Lp:= subs(d=NULL,L);

%p if Lp=[] or Lp[-1] = 0 then return false fi;

%p if not isprime(add(Lp[i]*10^(i-1),i=1..nops(Lp))) then return false fi;

%p od;

%p true

%p end proc:

%p select(filter, [seq(i,i=13..20000,2)]); # _Robert Israel_, Jul 13 2018

%Y Cf. A057877-A057883, A051362, A034302-A034305.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Oct 15 2000

%E Name edited by _Robert Israel_, Jul 13 2018

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Last modified November 27 03:16 EST 2021. Contains 349345 sequences. (Running on oeis4.)