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A104690 Smallest semiprime containing exactly n 4's. 0
4, 445, 4414, 44441, 444441, 4444441, 44444441, 444444449, 4444444441, 44444444443, 444444444447, 4444444444443, 44444444444441, 444444444444445, 4444444444444447, 44444444444444447, 444444444444444442 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

a(2)=445 because 445 is the smallest semiprime containing exactly two 4's.

CROSSREFS

Sequence in context: A217269 A034985 A262102 * A300507 A215220 A035483

Adjacent sequences:  A104687 A104688 A104689 * A104691 A104692 A104693

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, Apr 24 2005

STATUS

approved

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Last modified June 16 21:55 EDT 2021. Contains 345080 sequences. (Running on oeis4.)