A294885 a(n) = A004125(n) mod n = [Sum_{i=1..n} (n mod i)] mod n.

0, 0, 1, 1, 4, 3, 1, 0, 3, 3, 0, 5, 2, 3, 6, 4, 0, 11, 7, 1, 7, 11, 6, 13, 3, 8, 17, 12, 6, 18, 12, 7, 19, 27, 8, 18, 11, 20, 35, 18, 10, 32, 24, 20, 24, 36, 27, 38, 22, 20, 41, 38, 28, 6, 34, 16, 40, 56, 45, 46, 35, 52, 0, 53, 23, 65, 53, 51, 12, 65, 52, 60, 47, 68, 6, 4, 48, 22, 7, 46, 73, 15, 82, 11, 58, 83, 35, 15, 87, 17, 71, 71

Offset: 1

Author

Antti Karttunen, Nov 13 2017

Keywords

• nonn

Links

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

Crossrefs

Cf. A004125.

Cf. A056550 (positions of zeros).

Programs

Mathematica

Table[Mod[Sum[Mod[n,i],{i,n}],n],{n,100}] (* Harvey P. Dale, Jul 10 2024 *)

PARI

A294885(n) = (sum(k=2, n, n%k)%n);

Formula

a(n) = [Sum_{i=1..n} (n mod i)] mod n.