A393230 Numbers k such that sigma(k) = psi(k) + phi(k) + Omega(k)^3.

2288, 5168, 64220, 192712, 33736672, 66590464

Offset

1,1

Links

Table of n, a(n) for n=1..6.

Example

2288 is a term since sigma(2288) = 5208 = 4032 + 960 + 6^3 = psi(2288) + phi(2288) + Omega(2288)^3.

Prog

(PARI) isok(k) = {my(f = factor(k)); sigma(f) == prod(i=1, #f~, (f[i, 1]+1) * f[i, 1]^(f[i, 2]-1)) + eulerphi(f) + bigomega(f)^3; } \\ Amiram Eldar, Feb 06 2026

Crossrefs

Cf. A000203, A001615, A000010, A001222, A390049, A393229.

Sequence in context: A236700 A268892 A206663 * A247990 A206103 A251302

Adjacent sequences: A393227 A393228 A393229 * A393231 A393232 A393233

Keyword

nonn,hard,more

Author

S. I. Dimitrov, Feb 06 2026

Status

approved