OFFSET
1,1
LINKS
Donovan Johnson, Table of n, a(n) for n = 1..1000
PROG
(PARI) {op=vector(N=12); Nd6=N/6; for( n=1, 1e4, if( op[n%N+1]+0==op[n%N+1]=eulerphi(n), if ((n-N) % Nd6 != 0, print1(n-N, ", "))))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, Sep 27 2012
STATUS
approved