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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
23, 37, 53, 73, 113, 131, 137, 151, 173, 179, 197, 211, 311, 317, 431, 617, 719, 1531, 1831, 1997, 2113, 2131, 2237, 2273, 2297, 2311, 2797, 3137, 3371, 4337, 4373, 4733, 4919, 6173, 7297, 7331, 7573, 7873, 8191, 8311, 8831, 8837, 12239, 16673, 19531 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..1000

EXAMPLE

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

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

MAPLE

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

  if not isprime(n) then return false fi;

  L:= convert(n, base, 10);

  for d in convert(L, set) do

    Lp:= subs(d=NULL, L);

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

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

  od;

  true

end proc:

select(filter, [seq(i, i=13..20000, 2)]); # Robert Israel, Jul 13 2018

CROSSREFS

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

Sequence in context: A329262 A268343 A063643 * A244282 A051362 A034302

Adjacent sequences:  A057873 A057874 A057875 * A057877 A057878 A057879

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Oct 15 2000

EXTENSIONS

Name edited by Robert Israel, Jul 13 2018

STATUS

approved

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Last modified October 22 16:15 EDT 2021. Contains 348174 sequences. (Running on oeis4.)