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A219730 Sum_{x <= n} smallest divisor of x that is >= sqrt(x). 1
1, 3, 6, 8, 13, 16, 23, 27, 30, 35, 46, 50, 63, 70, 75, 79, 96, 102, 121, 126, 133, 144, 167, 173, 178, 191, 200, 207, 236, 242, 273, 281, 292, 309, 316, 322, 359, 378, 391, 399, 440, 447, 490, 501, 510, 533, 580, 588, 595, 605, 622, 635, 688, 697, 708, 716 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

G. Tenenbaum proved that a(n) is asymptotically equal to (Pi^2/12)*n^2/log(n) (Théorème 2). - Michel Marcus, Nov 26 2012

LINKS

Table of n, a(n) for n=1..56.

S. Flinch, Multiples and divisors, January 27, 2004. [Cached copy, with permission of the author]

G. Tenenbaum, Sur deux fonctions de diviseurs, J. London Math. Soc. (1976) s2-14 (3): 521-526.

CROSSREFS

Cf. A033677, A219729.

Sequence in context: A046669 A046670 A131383 * A139001 A090961 A073355

Adjacent sequences:  A219727 A219728 A219729 * A219731 A219732 A219733

KEYWORD

nonn

AUTHOR

Michel Marcus, Nov 26 2012

STATUS

approved

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Last modified December 12 01:08 EST 2017. Contains 295936 sequences.