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A188342 Smallest odd primitive abundant number (A006038) having n distinct prime factors. 2
945, 3465, 15015, 692835, 22309287, 1542773001, 33426748355, 1635754104985, 114761064312895, 9316511857401385, 879315530560980695 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

COMMENTS

Dickson proves that there are only a finite number of odd primitive abundant numbers having n distinct prime factors. For n=3, there are 8 such numbers: 945, 1575, 2205, 7425, 78975, 131625, 342225, 570375. See A188439.

a(14) <= 88452776289145528645. - Donovan Johnson, Mar 31 2011

LINKS

Table of n, a(n) for n=3..13.

L. E. Dickson, Finiteness of the odd perfect and primitive abundant numbers with n distinct prime factors, American Journal of Mathematics 35 (1913), pp. 413-422.

H. N. Shapiro, Note on a theorem of Dickson, Bull Amer. Math. Soc. 55 (4) (1949), 450-452

CROSSREFS

Sequence in context: A188439 A127667 A188263 * A109729 A127666 A133818

Adjacent sequences:  A188339 A188340 A188341 * A188343 A188344 A188345

KEYWORD

nonn,more

AUTHOR

T. D. Noe, Mar 28 2011

EXTENSIONS

a(8)-a(12) from Donovan Johnson, Mar 29 2011

a(13) from Donovan Johnson, Mar 31 2011

STATUS

approved

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Last modified April 17 06:56 EDT 2014. Contains 240634 sequences.