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A054014 Chowla function of n read modulo (the number of divisors of n). 5
0, 0, 0, 2, 0, 1, 0, 2, 0, 3, 0, 3, 0, 1, 0, 4, 0, 2, 0, 3, 2, 1, 0, 3, 2, 3, 0, 3, 0, 1, 0, 0, 2, 3, 0, 0, 0, 1, 0, 1, 0, 5, 0, 3, 2, 1, 0, 5, 1, 0, 0, 3, 0, 1, 0, 7, 2, 3, 0, 11, 0, 1, 4, 6, 2, 5, 0, 3, 2, 1, 0, 2, 0, 3, 0, 3, 2, 1, 0, 5, 4, 3, 0, 7, 2, 1, 0, 3, 0, 11, 0, 3, 2, 1, 0, 11, 0, 0, 2, 8, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Chowla's function (A048050) = sum of divisors of n except 1 and n.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..16384

FORMULA

a(n) = A048050(n) mod A000005(n).

MAPLE

with(numtheory): [seq((sigma(i)-i-1) mod tau(i), i=1..120)];

MATHEMATICA

Array[Mod[DivisorSigma[1, #] - # - 1, DivisorSigma[0, #]] &, 103] (* Michael De Vlieger, Oct 30 2017 *)

PROG

(PARI) A054014(n) = ((sigma(n)-n-1) % numdiv(n)); \\ Antti Karttunen, Oct 30 2017

CROSSREFS

Cf. A000005, A048050, A054013, A054015.

Sequence in context: A144764 A084929 A293575 * A158945 A156667 A178090

Adjacent sequences:  A054011 A054012 A054013 * A054015 A054016 A054017

KEYWORD

nonn

AUTHOR

Asher Auel (asher.auel(AT)reed.edu), Jan 17 2000

STATUS

approved

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Last modified August 14 09:14 EDT 2020. Contains 336480 sequences. (Running on oeis4.)