A054022 Chowla function of n is divisible by the number of divisors of n.

1, 2, 3, 5, 7, 9, 11, 13, 15, 17, 19, 23, 27, 29, 31, 32, 35, 36, 37, 39, 41, 43, 47, 50, 51, 53, 55, 59, 61, 67, 71, 73, 75, 79, 83, 87, 89, 91, 95, 97, 98, 101, 103, 107, 109, 111, 113, 115, 119, 123, 127, 131, 135, 137, 139, 143, 149, 151, 155, 157, 159, 162, 163

Offset

1,2

Comments

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

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Maple

with(numtheory):
[seq(`if`((sigma(i)-i-1) mod tau(i)=0, i, print( )), i=1..1000)];

Mathematica

Select[Range[200], Divisible[DivisorSigma[1, #]-1-#, DivisorSigma[0, #]]&] (* Harvey P. Dale, Mar 11 2012 *)

Crossrefs

Complement is A054023 Cf. A000005, A048050, A054014.

Sequence in context: A082664 A342008 A095737 * A185603 A046654 A280724

Adjacent sequences: A054019 A054020 A054021 * A054023 A054024 A054025

Keyword

nonn

Author

Asher Auel, Jan 19 2000

Status

approved