login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A262086 Numbers n such that phi(n + 10) = phi(n) + 10 where phi(n) = A000010(n) is Euler's totient function. 4
3, 7, 13, 19, 31, 36, 37, 43, 61, 73, 79, 97, 103, 127, 139, 157, 163, 181, 223, 229, 241, 271, 283, 307, 337, 349, 373, 379, 409, 421, 433, 439, 457, 499, 547, 577, 607, 631, 643, 673, 691, 709, 733, 751, 787, 811, 829, 853, 877, 919, 937, 967 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The only composite term less than 10^11 is 36. - Giovanni Resta, Sep 14 2015

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..1000

Wikipedia, Euler's totient function

EXAMPLE

3 is in the sequence since phi(13) = phi(3) + 10.

MATHEMATICA

Select[Range@1000, EulerPhi@(# + 10) == EulerPhi[#] + 10 &] (* Vincenzo Librandi, Sep 11 2015 *)

PROG

(MAGMA) [n: n in [1..1000] | EulerPhi(n+10) eq EulerPhi(n)+10]; // Vincenzo Librandi, Sep 11 2015

(PARI) is(n)=eulerphi(n + 10) == eulerphi(n) + 10 \\ Anders Hellström, Sep 11 2015

CROSSREFS

Cf. A000010, A023203.

Cf. A001838 (k=2), A056772 (k=4), A262084 (k=6), A262085 (k=8), this sequence (k=10).

Sequence in context: A031215 A099957 A086148 * A205956 A215907 A007645

Adjacent sequences:  A262083 A262084 A262085 * A262087 A262088 A262089

KEYWORD

nonn,easy

AUTHOR

Kevin J. Gomez, Sep 10 2015

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 17 03:06 EST 2019. Contains 329216 sequences. (Running on oeis4.)