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A392078

Numbers k such that sigma(k) = psi(k) + phi(k) + omega(k)^9.

786120, 7466772, 13995500, 14675968, 16055760, 18637080, 23941524, 41035260, 54282690, 55856680, 60484116, 61439124, 62574204, 68571090, 69111630, 70778964, 77774772, 96903876, 98065688, 103401100, 105680244, 108000084, 111629388, 130356380, 132309708, 141780510, 142694004, 148854860

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..28.

EXAMPLE

786120 is a term since sigma(786120) = 2358720 = 1886976 + 209600 + 4^9 = psi(786120) + phi(786120) + omega(786120)^9.

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) + omega(f)^9; } \\ Amiram Eldar, Dec 30 2025

CROSSREFS

Cf. A000203 (sigma), A001615 (psi), A000010 (phi), A001221 (omega), A390049, A391312, A391749, A391763, A391908, A391949, A389972, A392077.

Sequence in context: A206633 A184213 A205261 * A157993 A175747 A355707

Adjacent sequences: A392075 A392076 A392077 * A392079 A392080 A392081

KEYWORD

nonn

AUTHOR

S. I. Dimitrov, Dec 30 2025

EXTENSIONS

a(9)-a(28) from Amiram Eldar, Dec 30 2025

STATUS

approved

URL: https://oeis.org/A392078

⇱ A392078 - OEIS