A358489 Numbers k such that phi(k) = 13! where phi is the Euler totient function (A000010).

6227180929, 6227182993, 6227186509, 6227199361, 6227220691, 6227229637, 6227245393, 6227246107, 6227260969, 6227267713, 6227268799, 6227279341, 6227280491, 6227288461, 6227311397, 6227314111, 6227327761, 6227351861, 6227355097, 6227376241, 6227447761, 6227454979

Offset: 1

Author

Darío Clavijo, Nov 18 2022

Keywords

• nonn
• fini

Comments

A055487(13) = 6227180929 is the first term in the sequence.

A165774(13) = 37020293310 is the last term in the sequence.

Links

• Project Euler, Problem 248. Numbers for which Euler's totient function equals 13!.

Crossrefs

Cf. A000010, A055487, A165774.

Programs

Python

from sympy import totient
def isok(k): return totient(k) == 6227020800