login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A055970 Nonprime numbers k such that k | sigma_3(k) + phi(k)^3. 2
1, 195, 366, 735, 780, 810, 860, 1070, 1692, 2940, 3135, 5535, 6076, 7344, 13194, 15980, 20320, 37638, 47520, 54216, 62296, 89964, 95208, 121770, 135540, 135681, 138278, 138456, 140228, 140284, 158598, 161602, 162432, 189777, 205400, 268380 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..269 (terms below 10^10)

MATHEMATICA

Do[ If[ !PrimeQ[ n ], If[ Mod[ DivisorSigma[ 3, n ]+EulerPhi[ n ]^3, n ]==0, Print[ n ] ] ], {n, 1, 500000} ]

CROSSREFS

Cf. A000010, A001158, A055697.

Sequence in context: A351803 A080394 A323975 * A158225 A080913 A343339

Adjacent sequences:  A055967 A055968 A055969 * A055971 A055972 A055973

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jul 19 2000

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 6 16:34 EDT 2022. Contains 357270 sequences. (Running on oeis4.)