A393477 Numbers k such that sigma(k) = psi(k) + pi(k) + Omega(k)^10.

1, 119807919, 9534193025, 9534194075, 12043640675, 12436160275

Offset

1,2

Links

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

Example

119807919 is a term since sigma(119807919) = 215759232 = 199162368 + 6831239 + 5^10 = psi(119807919) + pi(119807919) + Omega(119807919)^10.

Prog

(PARI) dedpsi(f) = prod(k = 1, #f~, (f[k, 1]+1) * f[k, 1]^(f[k, 2]-1));
list(lim) = {my(q = 2, m = 0, f); print1(1, ", "); forprime(p = 3, lim, m++; for(k = q, p-1, f = factor(k); if(sigma(f) == dedpsi(f) + m + bigomega(f)^10, print1(k, ", "))); q = p); } \\ Amiram Eldar, Mar 24 2026

Crossrefs

Cf. A000203, A000720, A001615, A001222, A393162, A393163, A393123, A394260, A394312, A394315, A394402, A394403, A393550.

Sequence in context: A186804 A344632 A015380 * A250458 A038131 A081734

Adjacent sequences: A393474 A393475 A393476 * A393478 A393479 A393480

Keyword

nonn,hard,more

Author

S. I. Dimitrov, Mar 24 2026

Extensions

a(3)-a(6) from Amiram Eldar, Mar 25 2026

Status

approved