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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
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
KEYWORD
base,nonn
AUTHOR
Shyam Sunder Gupta, Apr 24 2005
STATUS
approved

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Last modified April 23 18:16 EDT 2024. Contains 371916 sequences. (Running on oeis4.)