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A121111
Trajectory of 277777788888899 under "x -> product of digits of x" map.
1
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
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
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