A160550 a(n) = A001065(n) mod A000005(n).

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

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 A331363 A359368

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