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A057880 Primes with 4 distinct digits that remain prime (no leading zeros allowed) after deleting all occurrences of its digits d. 2
6173, 12239, 16673, 19531, 19973, 21613, 22397, 22937, 34613, 36137, 47933, 51193, 54493, 56519, 56531, 56591, 69491, 69497, 72937, 76873, 93497, 96419, 96479, 96497, 98837, 112939, 118213, 131779, 143419, 144497, 159319, 163337 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..653

MAPLE

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

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

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

      for d in convert(L, set) do

        Lp:= remove(`=`, L, d);

        if Lp[-1] = 0 or not isprime(add(Lp[i]*10^(i-1), i=1..nops(Lp))) then return false fi;

      od;

      true

end proc:

getCands:= proc(n, m) option remember;

   if m = 1 then return [seq([d$n], d=0..9)] fi;

   if n < m then return [] fi;

   [seq(seq([i, op(L)], i= {$0..9} minus convert(L, set)), L = procname(n-1, m-1)),

    seq(seq([i, op(L)], i=convert(L, set)), L = procname(n-1, m))]

end proc:

[seq(op(sort(map(t->add(t[i]*10^(i-1), i=1..nops(t)), select(filter, getCands(d, 4))))), d=4..6)]; # Robert Israel, Jan 19 2017

MATHEMATICA

p4dQ[n_]:=Module[{idn=IntegerDigits[n]}, Count[idn, 0]==0 && Count[ DigitCount[ n], 0]==6&&AllTrue[FromDigits/@Table[DeleteCases[idn, k], {k, Union[idn]}], PrimeQ]]; Select[Prime[Range[15000]], p4dQ] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Sep 30 2017 *)

CROSSREFS

Cf. A057876-A057883, A051362, A034302-A034305.

Sequence in context: A007992 A033288 A266586 * A151967 A214556 A114930

Adjacent sequences:  A057877 A057878 A057879 * A057881 A057882 A057883

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Oct 15 2000

EXTENSIONS

Offset changed by Robert Israel, Jan 19 2017

STATUS

approved

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Last modified October 27 23:26 EDT 2020. Contains 338047 sequences. (Running on oeis4.)