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A051812 Number of n-digit numbers with nonzero multiplicative digital root 1. 1
1, 5, 24, 243, 3048, 35224, 374890, 3766188, 36537927, 348892847, 3315037530, 31399344551, 295789894509, 2769886220702, 25882768895688, 243033400452156 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Not counting zero as a one-digit number.
REFERENCES
William Mayne, sci.math, Jun 15 1991
LINKS
FORMULA
a(n) = # { i : 10^(n-1) < i < 10^n and A051802(i)=1 }.
CROSSREFS
Sequence in context: A120765 A259355 A297664 * A267279 A257214 A003224
KEYWORD
nonn,base,hard
AUTHOR
Dan Hoey, Dec 09 1999
STATUS
approved

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Last modified March 29 10:59 EDT 2024. Contains 371277 sequences. (Running on oeis4.)