A046517 Numbers with multiplicative persistence value 8.

2677889, 2677898, 2677988, 2678789, 2678798, 2678879, 2678897, 2678978, 2678987, 2679788, 2679878, 2679887, 2687789, 2687798, 2687879, 2687897, 2687978, 2687987, 2688779, 2688797, 2688977, 2689778, 2689787, 2689877

Offset

1,1

Links

Daniel Mondot, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Robert Israel)

Eric Weisstein's World of Mathematics, Multiplicative Persistence

Example

2677889 -> [ 338688 ][ 27648 ][ 2688 ][ 768 ][ 336 ][ 54 ][ 20 ][ 0 ] -> one digit in eight steps.

Maple

mp:= proc(n) option remember;
    if n <= 9 then return 0 fi;
    1+procname(convert(convert(n, base, 10), `*`))
end proc:
select(mp=8, [$1..4000000]); # Robert Israel, Feb 12 2019

Mathematica

okQ[n_]:=Length[NestWhileList[Times@@IntegerDigits[#]&, n, IntegerLength[ #]>1&]]==9; Select[Range[2700000], okQ]  (* Harvey P. Dale, Jan 29 2011 *)

Crossrefs

Cf. A003001, A014120, A046508.

Sequence in context: A147712 A250840 A121108 * A199998 A046508 A251457

Adjacent sequences: A046514 A046515 A046516 * A046518 A046519 A046520

Keyword

nonn,base

Author

Patrick De Geest, Sep 15 1998

Extensions

Offset corrected by Robert Israel, Feb 12 2019

Status

approved