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Revision History for A324048

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Showing entries 1-10 | older changes

A324048

a(n) = A000203(n) - A083254(n) = n + sigma(n) - 2*phi(n).
(history; published version)

#14 by Michel Marcus at Mon Dec 04 01:34:10 EST 2023

STATUS

reviewed

approved

#13 by Joerg Arndt at Mon Dec 04 01:10:12 EST 2023

STATUS

proposed

reviewed

#12 by Amiram Eldar at Mon Dec 04 01:05:22 EST 2023

STATUS

editing

proposed

#11 by Amiram Eldar at Mon Dec 04 01:03:20 EST 2023

FORMULA

Sum_{k=1..n} a(nk) = (Pi^2/12 - 6/Pi^2 + 1/2) * n^2 + O(n*log(n)). - Amiram Eldar, Dec 04 2023

#10 by Amiram Eldar at Mon Dec 04 00:45:25 EST 2023

	FORMULA	`a(n) = (Pi^2/12 - 6/Pi^2 + 1/2) * n^2 + O(n*log(n)). - Amiram Eldar, Dec 04 2023`
	MATHEMATICA	`a[n_] := n + DivisorSigma[1, n] - 2 * EulerPhi[n]; Array[a, 100] (* Amiram Eldar, Dec 04 2023 *)`
	PROG	`(PARI) a(n) = {my(f = factor(n)); n + sigma(f) - 2*eulerphi(f); } \\ Amiram Eldar, Dec 04 2023`
	KEYWORD	`nonn,easy`
	STATUS	`approved` `editing`

#9 by Susanna Cuyler at Thu Feb 14 07:47:20 EST 2019

STATUS

proposed

approved

#8 by Antti Karttunen at Wed Feb 13 17:16:24 EST 2019

STATUS

editing

proposed

#7 by Antti Karttunen at Wed Feb 13 17:12:39 EST 2019

FORMULA

a(n) = A000203(n) - A083254(n) = n + ( + A000203(n) - 2*A000010(n)).).

#6 by Antti Karttunen at Wed Feb 13 11:51:44 EST 2019

LINKS

Antti Karttunen, <a href="/A324048/b324048.txt">Table of n, a(n) for n = 1..20000</a>

#5 by Antti Karttunen at Wed Feb 13 11:43:24 EST 2019

FORMULA

a(n) = A297159(n) + 2*A001065(n).

CROSSREFS

Last modified September 11 16:20 EDT 2024. Contains 375836 sequences. (Running on oeis4.)