A139770 - OEIS

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A139770

Smallest number having at least as many divisors an n.

1, 2, 2, 4, 2, 6, 2, 6, 4, 6, 2, 12, 2, 6, 6, 12, 2, 12, 2, 12, 6, 6, 2, 24, 4, 6, 6, 12, 2, 24, 2, 12, 6, 6, 6, 36, 2, 6, 6, 24, 2, 24, 2, 12, 12, 6, 2, 48, 4, 12, 6, 12, 2, 24, 6, 24, 6, 6, 2, 60, 2, 6, 12, 24, 6, 24, 2, 12, 6, 24, 2, 60, 2, 6, 12, 12, 6, 24, 2, 48, 12, 6, 2, 60, 6, 6, 6, 24, 2 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	COMMENTS	`Similar to A140635, except that a(n) is allowed to have more divisors than n.` `a(n)<=n for all n. Moreover, a(n)=n if and only if n belongs to A061799 (or equivalently A002182).`
	FORMULA	`a(n) = A061799(A000005(n))`
	EXAMPLE	`16 has 5 divisors; smallest number with at least 5 divisors is 12 with 6 divisors`
	CROSSREFS	`Cf. A000005, A002182, A061799, A140635.` `Sequence in context: A074369 A073348 A122457 * A140635 A002322 A127835` `Adjacent sequences: A139767 A139768 A139769 * A139771 A139772 A139773`
	KEYWORD	`nonn`
	AUTHOR	`J. Lowell (jhbubby(AT)mindspring.com), May 20 2008`
	EXTENSIONS	`Edited and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), May 24 2008`

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Last modified February 15 18:22 EST 2012. Contains 205835 sequences.