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A136669 Primes of the form colossally abundant number - 1. 1
5, 11, 59, 359, 5039, 55439, 1441439, 135483209545341953934626770390607999, 21406347108164028721671029721716063999, 6223083124956116561507895939157782409673929631999, 78232234099885463677928129398618807521962436643076243437332696602750813193299417065162966120702842438719999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The n-th colossally abundant number - 1 is prime for n = 2, 3, 4, 6, 8, 9, 11, 34, 36, 43, 73, 81, 86, 115.

LINKS

Table of n, a(n) for n=1..11.

FORMULA

{A004490(i) - 1} INTERSECTION A000040.

EXAMPLE

A004490(11) = 1441440, and 1441440 - 1 = 1441439 is prime.

CROSSREFS

Cf. A000040, A004490, A181561, A181562.

Sequence in context: A104359 A104357 A104364 * A208768 A057824 A057822

Adjacent sequences:  A136666 A136667 A136668 * A136670 A136671 A136672

KEYWORD

nonn

AUTHOR

Jonathan Vos Post, Jan 31 2011

EXTENSIONS

a(11) from Charles R Greathouse IV, Oct 09 2011

STATUS

approved

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Last modified April 20 03:02 EDT 2021. Contains 343121 sequences. (Running on oeis4.)