A046506 Primes with multiplicative persistence value 6.

8867, 23887, 27883, 28387, 28837, 32887, 34487, 34847, 38287, 38447, 43487, 44647, 46447, 47843, 48437, 48473, 49999, 72883, 74843, 78283, 78823, 82387, 82837, 84347, 84437, 87443, 88237, 88327, 94999, 118687, 123887, 126487, 128467

Offset: 1

Author

Patrick De Geest, Sep 15 1998

Keywords

• nonn
• base

Examples

			8867 -> [ 2688 ][ 768 ][ 336 ][ 54 ][ 20 ][ 0 ] -> one digit in six steps.
		

Links

• Robert Israel, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Multiplicative Persistence

Crossrefs

Cf. A046500, A046515.

Programs

Maple

filter:= proc(n) local L,i;
  L:= convert(convert(n,base,10),`*`); if L < 10 then return false fi;
  for i from 2 to 5 do
     L:= convert(convert(L,base,10),`*`); if L < 10 then return false fi
    od;
  L:= convert(convert(L,base,10),`*`); evalb(L < 10)
end proc:
count:= 0: Res:= NULL;
p:= 11:
while count < 100 do
  p:= nextprime(p);
  if filter(p) then count:= count+1; Res:= Res,p fi
od:
Res; # Robert Israel, Jun 06 2018

Extensions

Offset corrected by Robert Israel, Jun 06 2018