A156061 - OEIS

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A156061

a(n) = product of ranks of distinct prime factors of n; where Rank(2)=1, ..., rank(prime_i)=i.

1, 2, 1, 3, 2, 4, 1, 2, 3, 5, 2, 6, 4, 6, 1, 7, 2, 8, 3, 8, 5, 9, 2, 3, 6, 2 (list; graph; refs; listen; history; internal format)

	OFFSET	`2,2`
	EXAMPLE	`n=14 = 2 * 7. rank(14)= rank(2)rank(7)= 14 = 4. n=168 = 2^3 * 3 * 7. rank(168)= rank(2)rank(3)rank(7) = 124 = 8.`
	CROSSREFS	`Cf. A007947, A000040` `Sequence in context: A035491 A108230 A061395 * A124172 A058933 A087470` `Adjacent sequences: A156058 A156059 A156060 * A156062 A156063 A156064`
	KEYWORD	`nonn`
	AUTHOR	`Ctibor O. Zizka (c.zizka(AT)email.cz), Feb 03 2009`

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Last modified February 17 19:13 EST 2012. Contains 206085 sequences.