The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A191621 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A191621

a(n) = ((n+1)^n-(n-1)^n)/2+1.
(history; published version)

#21 by Wesley Ivan Hurt at Mon Apr 26 14:54:03 EDT 2021

STATUS

editing

approved

#20 by Wesley Ivan Hurt at Mon Apr 26 14:53:53 EDT 2021

NAME

a(n) = ((n+1)^n-(n-1)^n)/2+1.

STATUS

approved

editing

#19 by Harvey P. Dale at Sun Oct 27 11:22:12 EDT 2019

STATUS

editing

approved

#18 by Harvey P. Dale at Sun Oct 27 11:22:08 EDT 2019

MATHEMATICA

Table[((n+1)^n-(n-1)^n)/2+1, {n, 20}] (* Harvey P. Dale, Oct 27 2019 *)

STATUS

approved

editing

#17 by Russ Cox at Fri Mar 30 18:52:45 EDT 2012

AUTHOR

_Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), _, Jun 14 2011

Discussion

Fri Mar 30

18:52

OEIS Server: https://oeis.org/edit/global/257

#16 by M. F. Hasler at Tue Jun 21 17:49:36 EDT 2011

STATUS

proposed

approved

#15 by M. F. Hasler at Tue Jun 21 17:49:19 EDT 2011

CROSSREFS

Cf. A000040.

#14 by M. F. Hasler at Tue Jun 21 17:48:40 EDT 2011

COMMENTS

The next prime in the sequence , after 2, 5 and 29, has at least 888 digits (n >= 349).

#13 by Klaus Brockhaus at Tue Jun 21 17:24:01 EDT 2011

COMMENTS

The next prime in the sequence has at least 888 digits (n >= 349).

#12 by Joerg Arndt at Wed Jun 15 12:35:24 EDT 2011

DATA

2, 5, 29, 273, 3377, 51013, 1048577, 908609, 18640961, 432891137, 10000000001, 11225320101, 321504185345, 100498283728818, 10079828372881, 343360783937537, 12627774819845669, 498676704524517377, 21046391759976988929, 945381827279671853057, 45032132922921758270917

Discussion

Wed Jun 15

12:36

Joerg Arndt: A motivation would certainly be welcome as this looks a bit like a "random" formula.
But I dare say this is at least well-defined and not overly contrived.

Tue Jun 21

17:22

Klaus Brockhaus: Well, not *overly* contrived, but stll unmotivated. I vote for rejecting.