The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A011755 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A011755

a(n) = Sum_{k=1..n} k*phi(k).
(history; published version)

#40 by Vaclav Kotesovec at Wed May 08 03:50:34 EDT 2024

STATUS

editing

approved

#39 by Vaclav Kotesovec at Wed May 08 03:48:18 EDT 2024

FORMULA

a(n) = Sum_{k=1..n} phi(k^2). - Vaclav Kotesovec, May 08 2024

STATUS

approved

editing

#38 by Alois P. Heinz at Tue Feb 21 14:39:00 EST 2023

STATUS

proposed

approved

#37 by Chai Wah Wu at Tue Feb 21 14:37:33 EST 2023

STATUS

editing

proposed

#36 by Chai Wah Wu at Tue Feb 21 14:37:27 EST 2023

PROG

(Python)

from sympy import totient

def A011755(n): return sum(k*totient(k) for k in range(1, n+1)) # Chai Wah Wu, Feb 21 2023

STATUS

approved

editing

#35 by N. J. A. Sloane at Fri May 29 12:40:26 EDT 2020

STATUS

editing

approved

#34 by N. J. A. Sloane at Fri May 29 12:40:25 EDT 2020

FORMULA

Asymptotically: a(n) ~ (2/Pi^2)*n^3. - Vladeta Jovovic, Jan 02 2003

STATUS

approved

editing

#33 by OEIS Server at Mon Sep 10 10:52:07 EDT 2018

LINKS

Seiichi Manyama, <a href="/A011755/b011755_1.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..2001 from Indranil Ghosh)

#32 by Bruno Berselli at Mon Sep 10 10:52:07 EDT 2018

STATUS

proposed

approved

Discussion

Mon Sep 10

10:52

OEIS Server: Installed new b-file as b011755.txt.  Old b-file is now b011755_1.txt.

#31 by Vaclav Kotesovec at Mon Sep 10 10:51:17 EDT 2018

STATUS

editing

proposed