A395402 Numbers k such that sigma(k) = psi(k) + tau(k)^2 + Omega(k)^2.

352, 513, 532, 792, 1197, 3325, 16093, 20577, 22477, 38437, 70357, 111853, 127813, 182077, 223573, 245917, 293797, 373597, 462973, 494893, 597037, 670453, 708757, 830053, 916237, 1053493, 1251397, 1356733, 1410997, 1522717, 1580173, 1698277, 2145157, 2282413, 2496277, 2569693, 2952733, 3032533

Offset

1,1

Links

Table of n, a(n) for n=1..38.

Example

352 is a term since sigma(352) = 756 = 576 + 12^2 + 6^2 = psi(352) + tau(352)^2 + Omega(352)^2.

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)) + numdiv(f)^2 + bigomega(f)^2; } \\ Amiram Eldar, Apr 21 2026

Crossrefs

Cf. A000005, A000203, A001615, A001222, A394658.

Sequence in context: A167820 A145633 A252250 * A235888 A256025 A256771

Adjacent sequences: A395399 A395400 A395401 * A395403 A395404 A395405

Keyword

nonn

Author

S. I. Dimitrov, Apr 21 2026

Status

approved