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A163163 a(n) = sigma(n) + tau(n) - n. 2
1, 3, 3, 6, 3, 10, 3, 11, 7, 12, 3, 22, 3, 14, 13, 20, 3, 27, 3, 28, 15, 18, 3, 44, 9, 20, 17, 34, 3, 50, 3, 37, 19, 24, 17, 64, 3, 26, 21, 58, 3, 62, 3, 46, 39, 30, 3, 86, 11, 49, 25, 52, 3, 74, 21, 72, 27, 36, 3, 120, 3, 38, 47, 70, 23, 86, 3, 64, 31, 82, 3, 135, 3, 44, 55, 70, 23, 98, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

Antti Karttunen, Sequence plotted up to n=10000, showing the details better

FORMULA

a(n) = A007503(n) - n = A000203(n) + A000005(n) - n.

a(n) = A000005(n) + A001065(n). - Antti Karttunen, Feb 25 2018

EXAMPLE

a(10) = A007503(10) - 10 = 22 - 10 = 12.

MATHEMATICA

Table[Apply[Plus, DivisorSigma[#, n] & /@ {0, 1}] - n, {n, 79}] (* Michael De Vlieger, Feb 25 2018 *)

PROG

(PARI) A163163(n) = (sigma(n)+numdiv(n)-n); \\ Antti Karttunen, Feb 25 2018

CROSSREFS

Cf. A000005, A000027, A000203, A001065, A007503.

Sequence in context: A058587 A196439 A184389 * A323349 A307982 A120909

Adjacent sequences:  A163160 A163161 A163162 * A163164 A163165 A163166

KEYWORD

nonn,easy

AUTHOR

Juri-Stepan Gerasimov, Jul 22 2009

EXTENSIONS

47 replaced with 37 by R. J. Mathar, Jul 25 2009

STATUS

approved

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Last modified August 24 18:12 EDT 2019. Contains 326295 sequences. (Running on oeis4.)