A121111 Trajectory of 277777788888899 under "x -> product of digits of x" map.

277777788888899, 4996238671872, 438939648, 4478976, 338688, 27648, 2688, 768, 336, 54, 20, 0

Offset

1,1

Comments

This is the smallest number of persistence 11 (cf. A003001). It is conjectured that no number has persistence greater than 11.

Links

Table of n, a(n) for n=1..12.

N. J. A. Sloane, The persistence of a number, J. Recreational Math., 6 (1973), 97-98.

Formula

a(n)=A121110(n-1), n>=3. [From R. J. Mathar, Aug 07 2008]

Mathematica

NestWhileList[Times@@IntegerDigits[#]&, 277777788888899, #>0&] (* Harvey P. Dale, Nov 25 2022 *)

Crossrefs

Cf. A003001.

Sequence in context: A216906 A229383 A172596 * A352532 A179660 A080125

Adjacent sequences: A121108 A121109 A121110 * A121112 A121113 A121114

Keyword

nonn,fini,full,base

Author

N. J. A. Sloane, Aug 12 2006

Extensions

Edited by Charles R Greathouse IV, Aug 05 2010

Status

approved