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A131931 Smallest number containing exactly n prime factors in its decimal representation. 2
1, 2, 132, 735, 21372, 271362, 4773132, 113678565, 11317129824 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
A131929(a(n)) = n and A131929(m) <> n for m<a(n).
LINKS
EXAMPLE
a(2) = 2^2 * 3 * 11 = 132 containing 2 and 3;
a(3) = 3 * 5 * 7^2 = 735 containing 3, 5 and 7;
a(4) = 2^2 * 3 * 13 * 137 = 21372 containing 2, 3, 13 and 137;
a(5) = 2 * 3 * 7^2 * 13 * 71 = 271362 containing 2, 3, 7, 13 and 71.
CROSSREFS
Sequence in context: A119778 A071606 A080282 * A020524 A157071 A174585
KEYWORD
nonn,base,more
AUTHOR
Reinhard Zumkeller, Jul 30 2007
EXTENSIONS
Offset changed by and a(6)-a(8) from Giovanni Resta, Sep 06 2018
STATUS
approved

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Last modified May 28 00:20 EDT 2024. Contains 372900 sequences. (Running on oeis4.)