The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A334670

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

A334670

a(n) = (2*n+1)!! * (Sum_{k=1..n} 1/(2*k+1)).
(history; published version)

#33 by Bruno Berselli at Thu Apr 29 04:33:44 EDT 2021

STATUS

reviewed

approved

#32 by Joerg Arndt at Thu Apr 29 03:52:39 EDT 2021

STATUS

proposed

reviewed

#31 by Amiram Eldar at Thu Apr 29 02:36:54 EDT 2021

STATUS

editing

proposed

#30 by Amiram Eldar at Thu Apr 29 02:17:01 EDT 2021

MATHEMATICA

a[n_] := (2*n + 1)!! * Sum[1/(2*k + 1), {k, 1, n}]; Array[a, 21, 0] (* Amiram Eldar, Apr 29 2021 *)

STATUS

approved

editing

#29 by R. J. Mathar at Tue Sep 22 05:49:33 EDT 2020

STATUS

editing

approved

#28 by R. J. Mathar at Tue Sep 22 05:49:29 EDT 2020

FORMULA

P-finite with recurrence a(n) = 4*n*a(n-1) - (2*n-1)^2 * a(n-2) for n>1.

STATUS

approved

editing

#27 by Joerg Arndt at Sat Sep 12 02:36:32 EDT 2020

STATUS

proposed

approved

#26 by Seiichi Manyama at Sat Sep 12 02:33:33 EDT 2020

STATUS

editing

proposed

#25 by Seiichi Manyama at Sat Sep 12 02:33:14 EDT 2020

CROSSREFS

Column k=1 of A335095.

STATUS

reviewed

editing

#24 by Michel Marcus at Sat Sep 12 00:28:06 EDT 2020

STATUS

proposed

reviewed