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A160550 a(n) = A001065(n) mod A000005(n). 1
0, 1, 1, 0, 1, 2, 1, 3, 1, 0, 1, 4, 1, 2, 1, 0, 1, 3, 1, 4, 3, 2, 1, 4, 0, 0, 1, 4, 1, 2, 1, 1, 3, 0, 1, 1, 1, 2, 1, 2, 1, 6, 1, 4, 3, 2, 1, 6, 2, 1, 1, 4, 1, 2, 1, 0, 3, 0, 1, 0, 1, 2, 5, 0, 3, 6, 1, 4, 3, 2, 1, 3, 1, 0, 1, 4, 3, 2, 1, 6, 0, 0, 1, 8, 3, 2, 1, 4, 1, 0, 1, 4, 3, 2, 1, 0, 1, 1, 3, 0, 1, 2, 1, 2, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

COMMENTS

A054022(n) for n > 1 gives the numbers k such that a(k) = 1.

LINKS

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

MATHEMATICA

Table[Mod[DivisorSigma[1, n]-n, DivisorSigma[0, n]], {n, 110}] (* Harvey P. Dale, Jun 22 2013 *)

PROG

(MAGMA) [ (SumOfDivisors(n)-n) mod NumberOfDivisors(n): n in [1..105] ]; // Klaus Brockhaus, May 21 2009

(PARI) A160550(n)=lift(Mod(sigma(n)-n, numdiv(n))); \\ Michael B. Porter, Oct 13 2009

CROSSREFS

Cf. A000203, A000027, A000005, A054022, A001065, A003601, A140480.

Sequence in context: A117778 A072127 A186976 * A172038 A226131 A199056

Adjacent sequences:  A160547 A160548 A160549 * A160551 A160552 A160553

KEYWORD

easy,nonn

AUTHOR

Ctibor O. Zizka, May 19 2009

EXTENSIONS

Extended and comment edited by Klaus Brockhaus, May 21 2009

STATUS

approved

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Last modified December 15 00:30 EST 2019. Contains 329988 sequences. (Running on oeis4.)