A324215 Sequence lists numbers k > 1 such that k^3 == phi(k) (mod sigma(k)), where phi = A000010 and sigma = A000203.

5472, 10120, 22140, 66288, 84788, 97320, 125400, 152928, 244736, 245232, 364782, 769248, 839970, 910336, 1358046, 1390872, 1472748, 1593036, 4716640, 7672032, 11178612, 17984160, 31121640, 31535120, 31963680, 32749752, 34889400, 43949640, 45123880, 46978020

Offset

1,1

Links

Table of n, a(n) for n=1..30.

Formula

Solutions of k^3 mod sigma(k) = phi(k).

Example

sigma(5472) = 16380 and 5472^3 mod 16380 = 1728 = phi(5472).

Maple

with(numtheory): op(select(n->n^3 mod sigma(n)=phi(n), [$1..1593036]));

Crossrefs

Cf. A000010, A000203, A324214, A324216.

Sequence in context: A231269 A232037 A202776 * A234685 A031572 A045108

Adjacent sequences: A324212 A324213 A324214 * A324216 A324217 A324218

Keyword

nonn,easy

Author

Paolo P. Lava, Feb 18 2019

Extensions

a(20)-a(30) from Giovanni Resta, Feb 19 2019

Status

approved