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A051813 Number of n-digit numbers with nonzero multiplicative digital root 2. 1
1, 15, 208, 2389, 24845, 243697, 2348885, 22837227, 226507501, 2285904554, 23239957877, 235731610792, 2372897841904, 23686630752065, 235058927877399, 2327977363798607 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

William Mayne, sci.math, Jun 15 1991

LINKS

Table of n, a(n) for n=1..16.

FORMULA

# { i : 10^(n-1) < i < 10^n and A051802(i)=2 }

CROSSREFS

Cf. A051802, A051804, A051822.

Sequence in context: A194481 A078265 A089138 * A239991 A028230 A122572

Adjacent sequences:  A051810 A051811 A051812 * A051814 A051815 A051816

KEYWORD

nonn,base,hard

AUTHOR

Dan Hoey, Dec 09 1999

STATUS

approved

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Last modified November 28 06:47 EST 2014. Contains 250285 sequences.