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A081248

Number of numbers k<=n with mu(k+n)+mu(k)=0, where mu=A008683 (Moebius function).
(history; published version)

#6 by Harvey P. Dale at Fri Oct 06 20:05:12 EDT 2017

STATUS

editing

approved

#5 by Harvey P. Dale at Fri Oct 06 20:05:08 EDT 2017

MATHEMATICA

Table[Total[Table[If[MoebiusMu[k+n]+MoebiusMu[n]==0, 1, 0], {n, k}]], {k, 80}] (* Harvey P. Dale, Oct 06 2017 *)

STATUS

approved

editing

#4 by Russ Cox at Fri Mar 30 18:50:31 EDT 2012

AUTHOR

_Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), _, Mar 12 2003

Discussion
Fri Mar 30	18:50	OEIS Server: https://oeis.org/edit/global/246

#3 by N. J. A. Sloane at Fri Feb 27 03:00:00 EST 2009

EXAMPLE

n=10: mu(1+10)+mu(1)=(-1)+1, mu(5+10)+mu(5)=1+(-1), mu(8+10)+mu(8)=0+0, and mu(k+10)+mu(k)<>0 for k in {2,3,4,6,7,9,10}, therefore a(10)=3.

KEYWORD

nonn,new

nonn

#2 by N. J. A. Sloane at Fri Jan 09 03:00:00 EST 2009

KEYWORD

nonn,new

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystemsgmail.com), Mar 12 2003

#1 by N. J. A. Sloane at Fri May 16 03:00:00 EDT 2003

	NAME	`Number of numbers k<=n with mu(k+n)+mu(k)=0, where mu=A008683 (Moebius function).`
	DATA	`1, 1, 1, 3, 2, 1, 3, 4, 2, 3, 4, 6, 5, 2, 6, 9, 5, 5, 7, 9, 6, 7, 7, 9, 6, 6, 11, 14, 9, 6, 10, 18, 11, 8, 10, 20, 10, 12, 12, 21, 12, 6, 11, 25, 19, 14, 11, 22, 11, 16, 19, 27, 12, 16, 18, 28, 15, 17, 16, 23, 11, 16, 26, 32, 18, 16, 19, 34, 21, 18, 20, 43, 18, 23, 31, 41, 22, 16, 20, 45`
	OFFSET	`1,4`
	EXAMPLE	`n=10: mu(1+10)+mu(1)=(-1)+1, mu(5+10)+mu(5)=1+(-1), mu(8+10)+mu(8)=0+0, and mu(k+10)+mu(k)<>0 for k in {2,3,4,6,7,9,10}, therefore a(10)=3.`
	CROSSREFS	`Cf. A081247.`
	KEYWORD	`nonn`
	AUTHOR	`Reinhard Zumkeller (reinhard.zumkeller(AT)lhsystems.com), Mar 12 2003`
	STATUS	`approved`

Last modified August 30 00:57 EDT 2024. Contains 375520 sequences. (Running on oeis4.)