OFFSET
1,1
COMMENTS
See also the Cohen-te Riele links under A019276.
No other terms < 5*10^11. - Jud McCranie, Feb 08 2012
a(11) > 4*10^12, if it exists. - Giovanni Resta, Feb 26 2020
LINKS
G. L. Cohen and H. J. J. te Riele, Iterating the sum-of-divisors function, Experimental Mathematics, 5 (1996), pp. 93-100.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
EXTENSIONS
More terms from Jud McCranie, Nov 13 2001; a(9) Jan 29 2012, a(10) Feb 08 2012
STATUS
approved