cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A136669 Primes of the form colossally abundant number - 1.

Original entry on oeis.org

5, 11, 59, 359, 5039, 55439, 1441439, 135483209545341953934626770390607999, 21406347108164028721671029721716063999, 6223083124956116561507895939157782409673929631999, 78232234099885463677928129398618807521962436643076243437332696602750813193299417065162966120702842438719999
Offset: 1

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Author

Jonathan Vos Post, Jan 31 2011

Keywords

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.

Examples

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

Crossrefs

Cf. A000040, A004490, A181561, A181562.

Formula

{A004490(i) - 1} INTERSECTION A000040.

Extensions

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

A176903 Primes of the form colossally abundant number + 1.

Original entry on oeis.org

3, 7, 13, 61, 2521, 55441, 4324321, 367567201, 6064949221531201, 9200527969062830401, 37188534050951960476801, 8201519488959040182625924708238885435575055666675808001
Offset: 1

Views

Author

Jonathan Vos Post, Jan 31 2011

Keywords

Comments

The next term is too large to be displayed here.
The n-th colossally abundant number + 1 is prime for n = 1, 2, 3, 4, 7, 9, 12, 14, 21, 23, 26, 46, 65, 69, 143, 147.

Examples

			A004490(12) = 4324320, and 4324320 + 1 = 4324321 is prime.
A004490(46) + 1 = 8201519488959040182625924708238885435575055666675808001 is prime.

Crossrefs

Cf. A000040, A004490, A136669, A181561, A181562.

Formula

{A004490(i) + 1} INTERSECTION A000040.
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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