A392263 Numbers k such that sigma(k) = psi(k) + tau(k) + omega(k)^3.

52, 117, 325, 637, 1573, 3757, 4693, 6877, 10933, 12493, 17797, 21853, 24037, 28717, 36517, 45253, 48373, 58357, 65533, 69277, 81133, 89557, 102973, 122317, 132613, 137917, 148837, 154453, 165997, 209677, 223093, 243997, 251173, 288613, 296413, 320437, 345397, 362557, 389077, 416533, 425893, 474253, 484237

Offset

1,1

Comments

13*p^2 is a term for all primes p <> 13. - Marco Zárate, Jul 03 2026

Links

Table of n, a(n) for n=1..43.

Example

52 is a term since sigma(52) = 98 = 84 + 6 + 2^3 = psi(52) + tau(52) + omega(52)^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)) + numdiv(f) + omega(f)^3; } \\ Amiram Eldar, Jan 05 2026

Crossrefs

Cf. A000203 (sigma), A001615 (psi), A000005 (tau), A001221 (omega), A386637, A394738.

Sequence in context: A209988 A326912 A327147 * A346898 A120534 A122166

Adjacent sequences: A392260 A392261 A392262 * A392264 A392265 A392266

Keyword

nonn,changed

Author

S. I. Dimitrov, Jan 05 2026

Status

approved