A072490 - OEIS

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A072490

Number of squarefree numbers less than n.

0, 0, 1, 2, 2, 3, 4, 5, 5, 5, 6, 7, 7, 8, 9, 10, 10, 11, 11, 12, 12, 13, 14, 15, 15, 15, 16, 16, 16, 17, 18, 19, 19, 20, 21, 22, 22, 23, 24, 25, 25, 26, 27, 28, 28, 28, 29, 30, 30, 30, 30, 31 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,4`
	EXAMPLE	`a(10) = 5 as the squarefree numbers less than 10 are 2,3,5,6 and 7.`
	CROSSREFS	`a(n) = A013928(n)-1, n>1.` `Sequence in context: A135585 A081094 A054633 * A085972 A136378 A099249` `Adjacent sequences: A072487 A072488 A072489 * A072491 A072492 A072493`
	KEYWORD	`nonn`
	AUTHOR	`Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Jul 14 2002`

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Last modified February 17 11:46 EST 2012. Contains 206011 sequences.