OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..72
MATHEMATICA
Select[Range[10^6], EulerPhi[#]+EulerPhi[#+1]==#+2&] (* Harvey P. Dale, Apr 04 2019 *)
PROG
(PARI) isok(n) = eulerphi(n) + eulerphi(n+1) == n+2; \\ Michel Marcus, Nov 23 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Feb 07 2002
EXTENSIONS
More terms from Michel Marcus, Nov 23 2013
STATUS
approved