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A106663 Smallest semiprime ending in 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 A104775? - Andrew S. Plewe, Apr 11 2007

LINKS

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

EXAMPLE

a(3)=5999 is a term because 5999 is the smallest semiprime ending in exactly three 9's.

CROSSREFS

Sequence in context: A061685 A183549 A104775 * A196694 A196727 A197067

Adjacent sequences:  A106660 A106661 A106662 * A106664 A106665 A106666

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, May 12 2005

STATUS

approved

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Last modified February 22 23:44 EST 2020. Contains 332157 sequences. (Running on oeis4.)