A046508 Primes with multiplicative persistence value 8.

2678789, 2687879, 2687897, 2688797, 2688977, 2689877, 2697887, 2768789, 2768897, 2769887, 2778689, 2786789, 2787689, 2788769, 2798687, 2798867, 2868779, 2868977, 2876789, 2876879, 2878679, 2878697, 2878769, 2879687

Offset

1,1

Links

Daniel Mondot, Table of n, a(n) for n = 1..10000 (terms 1..9001 from Harvey P. Dale)

Eric Weisstein's World of Mathematics, Multiplicative Persistence

Example

2678789 -> [ 338688 ][ 27648 ][ 2688 ][ 768 ][ 336 ][ 54 ][ 20 ][ 0 ] -> one digit in eight steps.

Mathematica

mp8Q[n_]:=Length[NestWhileList[Times@@IntegerDigits[#]&, n, #>9&]]==9; Select[ Prime[ Range[210000]], mp8Q] (* Harvey P. Dale, Mar 30 2019 *)

Crossrefs

Intersection of A000040 and A046517.

Cf. A046500.

Sequence in context: A121108 A046517 A199998 * A251457 A178291 A212231

Adjacent sequences: A046505 A046506 A046507 * A046509 A046510 A046511

Keyword

nonn,base

Author

Patrick De Geest, Sep 15 1998

Status

approved