A393529 Numbers k such that sigma(k) = psi(k) + phi(k) + Omega(k)^7.

1631560, 2074884, 2568804, 2642892, 2720508, 3585736, 5008812, 5265444, 5283460, 5810628, 5820324, 5848068, 5945172, 5952108, 6185032, 6977300, 6991356, 7497816, 7524588, 7706020, 7827252, 8636244, 10070536, 10828236, 11721220, 12276708, 12681204, 13296136, 14153532, 14913220, 16562260, 17152072

Offset

1,1

Links

Michael S. Branicky, Table of n, a(n) for n = 1..240

Example

1631560 is a term since sigma(1631560) = 4196160 = 3356928 + 559296 + 6^7 = psi(1631560) + phi(1631560) + Omega(1631560)^7.

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)^7; } \\ Amiram Eldar, Feb 19 2026

Crossrefs

Cf. A000203, A001615, A000010, A001222, A390049, A393229, A393230, A393425, A391448, A393528.

Sequence in context: A173428 A015334 A015377 * A296450 A255042 A255035

Adjacent sequences: A393526 A393527 A393528 * A393530 A393531 A393532

Keyword

nonn

Author

S. I. Dimitrov, Feb 18 2026

Status

approved