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A132420 a(n) = the (2n)th positive divisor of n!. 0
24, 15, 16, 16, 20, 24, 27, 27, 30, 30, 33, 36, 40, 40, 44, 44, 48, 50, 52, 52, 55, 57, 63, 65, 68, 68, 70, 70, 75, 77, 80, 84, 87, 87, 90, 92, 95, 95, 98, 98, 100, 104, 108, 108, 111, 114, 116, 119, 121, 121, 124, 126, 129, 132, 135, 135, 138, 138, 141, 144, 147, 150 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,1

LINKS

Table of n, a(n) for n=4..65.

EXAMPLE

The positive divisors of 5! = 120 are 1,2,3,4,5,6,8,10,12,15,20,24,30,40,60,120. a(5) is the 10th of these, which is 15.

MATHEMATICA

a = {}; For[n = 4, n < 70, n++, i = 1; c = 0; While[c < 2n, If[Mod[n!, i] == 0, c++ ]; i++ ]; AppendTo[a, i - 1]]; a (* Stefan Steinerberger, Nov 24 2007 *)

CROSSREFS

Sequence in context: A075605 A334219 A118661 * A171907 A109475 A105191

Adjacent sequences:  A132417 A132418 A132419 * A132421 A132422 A132423

KEYWORD

nonn

AUTHOR

Leroy Quet, Nov 20 2007

EXTENSIONS

Corrected and extended by Stefan Steinerberger, Nov 24 2007

STATUS

approved

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Last modified September 29 15:17 EDT 2020. Contains 337432 sequences. (Running on oeis4.)