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A068421
Numbers n such that sigma(n) = 6*(n - phi(n)).
0
OFFSET
1,1
COMMENTS
No other term < 3500000. - Emeric Deutsch, Mar 08 2006
a(4) > 10^12. - Giovanni Resta, Nov 03 2012
MAPLE
with(numtheory): a:=proc(n) if sigma(n)=6*(n-phi(n)) then n else fi end: seq(a(n), n=1..5000); # Emeric Deutsch, Mar 08 2006
CROSSREFS
Sequence in context: A256070 A203339 A253690 * A142535 A203475 A203701
KEYWORD
more,nonn,bref
AUTHOR
Benoit Cloitre, Mar 02 2002
STATUS
approved