id:A018254 - OEIS Search Results

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Divisors of 28.

+0
10

1, 2, 4, 7, 14, 28 (list; graph; listen)

	OFFSET	`1,2`
	COMMENT	`28 is the second perfect number A000396(2) and 7 is the second Mersenne prime A000668(2). For the structure of this sequence and its representation in base 2, see A135652. - Omar E. Pol (info(AT)polprimos.com), Mar 03 2008`
	FORMULA	`a(n) = A161713(n-1). [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jun 21 2009]`
	CROSSREFS	`Cf. A000396, A000668, A135652.` `Sequence in context: A094057 A119267 A144978 this_sequence A018660 A018692 A161713` `Adjacent sequences: A018251 A018252 A018253 this_sequence A018255 A018256 A018257`
	KEYWORD	`nonn,fini,full`
	AUTHOR	`N. J. A. Sloane (njas(AT)research.att.com).`

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.