OFFSET
1,2
COMMENTS
Next term is greater than 135*10^7.
a(4) > 4*10^12. - Giovanni Resta, Apr 09 2017
EXAMPLE
a(3)=3902496 because pi(3902496)+sigma(3902496)=3*3902496 and 3902496 is the smallest such number.
CROSSREFS
KEYWORD
hard,more,nonn,less,bref
AUTHOR
Farideh Firoozbakht, Apr 11 2008
STATUS
approved