A346423 Numbers m such that Sum_{k=1..m} omega(k) = sigma(m).

11, 230, 52830, 160908, 6134334960

Offset

1,1

Comments

Numbers k such that A013939(k) = sigma(k).

Links

Table of n, a(n) for n=1..5.

Example

The sum of number of distinct primes dividing numbers up to 11 is 1+1+1+1+2+1+1+1+2+1 = sigma(11), so 11 is a term.

Mathematica

s=0; Do[s=s+PrimeNu[n]; If[DivisorSigma[1, n]==s, Print[n]], {n, 2, 160908}]

Crossrefs

Cf. A000203, A013939.

Sequence in context: A305141 A296592 A108518 * A077736 A068122 A015287

Adjacent sequences: A346420 A346421 A346422 * A346424 A346425 A346426

Keyword

nonn,more

Author

Metin Sariyar, Jul 16 2021

Extensions

a(5) from Martin Ehrenstein, Aug 22 2021

Status

approved