A076649 - OEIS

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A076649

Number of digits required to write the prime factors of n.

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

	OFFSET	`2,3`
	FORMULA	`a(n) is completely additive: a(mn)=a(m)+a(n) for all integers m, n>=1; with a(1)=0 and a(p^e)=efloor(log10(10*p)), p prime. - Diego Torres (torresvillarroel(AT)hotmail.com), Oct 26 2002` `Totally additive with a(p) = A055642(p).`
	EXAMPLE	`12=223 so a(12)=3`
	CROSSREFS	`Sequence in context: A050379 A153024 A066921 * A157235 A086289 A077807` `Adjacent sequences: A076646 A076647 A076648 * A076650 A076651 A076652`
	KEYWORD	`base,nonn`
	AUTHOR	`Jeff Burch (gburch(AT)erols.com), Oct 24 2002`

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Last modified February 17 11:35 EST 2012. Contains 206011 sequences.