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!)
A131826 a(n) is the unique solution to Cototient(x) = A131825(n). 7
1, 4, 9, 25, 10, 26, 34, 38, 30, 52, 74, 76, 82, 122, 90, 134, 146, 148, 114, 130, 194, 202, 206, 170, 226, 244, 186, 268, 292, 228, 290, 386, 388, 398, 404, 412, 370, 482, 366, 488, 434, 514, 430, 584, 518, 578, 614, 626, 450, 674, 462, 580, 610, 746, 558, 772 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
EXAMPLE
a(5) = 10 is the unique solution to Cototient(x) = A131825(5) = 6.
PROG
(PARI) lista(nn) = {my(c, r, v=vector(nn^2+2, i, i - eulerphi(i))); for(k=0, nn, c=0; for(i=1, k*k+2, if(k==v[i], r=i; c++)); if(c==1, print1(r, ", "))); } \\ Jinyuan Wang, Mar 22 2020
CROSSREFS
Sequence in context: A334656 A175121 A133905 * A366786 A051961 A339794
KEYWORD
nonn
AUTHOR
Franz Vrabec, Jul 20 2007
EXTENSIONS
More terms from Jinyuan Wang, Mar 22 2020
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 March 3 08:08 EST 2024. Contains 370499 sequences. (Running on oeis4.)