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A104775 Smallest semiprime containing exactly n 9's. 1
9, 299, 5999, 19999, 899999, 5999999, 79999999, 299999999, 1999999999, 49999999999, 499999999999, 1999999999999, 29999999999999, 199999999999999, 1999999999999999, 29999999999999999, 599999999999999999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

When (if ever) does this differ from A106663? - Andrew S. Plewe, Apr 11 2007

LINKS

Table of n, a(n) for n=1..17.

EXAMPLE

a(2)=299 because 299 is the smallest semiprime containing exactly two 9's.

CROSSREFS

Sequence in context: A211082 A061685 A183549 * A106663 A196694 A196727

Adjacent sequences:  A104772 A104773 A104774 * A104776 A104777 A104778

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Apr 24 2005

STATUS

approved

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Last modified February 27 07:04 EST 2020. Contains 332299 sequences. (Running on oeis4.)