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!)
A046078 Primes of the form n*phi(n)-1 where phi is the Euler function (in order of appearance). 3
5, 7, 19, 11, 41, 31, 53, 109, 47, 83, 127, 271, 107, 251, 191, 499, 311, 811, 239, 929, 659, 839, 431, 683, 503, 2161, 971, 3659, 2267, 3119, 1319, 4421, 4969, 2663, 2999, 1871, 4373, 4871, 6551, 9311, 5939, 10099, 5039, 8423, 11423, 13309, 9839, 16001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These are listed in order of increasing n.

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

MAPLE

op(map(proc(n) n*phi(n)-1 end, select(n->isprime(n*phi(n)-1), [$1..127]))); # Paolo P. Lava, Jul 31 2018

MATHEMATICA

Select[Table[n EulerPhi[n]-1, {n, 250}], PrimeQ[#]&] (* Harvey P. Dale, Aug 15 2011 *)

CROSSREFS

Cf. A059109.

Cf. A002618, A046062

Sequence in context: A116623 A349170 A046151 * A075409 A258655 A174362

Adjacent sequences: A046075 A046076 A046077 * A046079 A046080 A046081

KEYWORD

easy,nice,nonn

AUTHOR

Felice Russo

EXTENSIONS

Corrected and extended by Jud McCranie, Jan 03 2001

Name clarified by Michel Marcus, Jul 31 2018

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 February 7 02:40 EST 2023. Contains 360111 sequences. (Running on oeis4.)