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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

Table of n, a(n) for n=0..8.

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

Cf. A131930, A131929, A318965.

Sequence in context: A119778 A071606 A080282 * A020524 A157071 A174585

Adjacent sequences:  A131928 A131929 A131930 * A131932 A131933 A131934

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 December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)