OFFSET
1,1
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..40
MATHEMATICA
NestList[DivisorSigma[1, #]DivisorSigma[0, #]&, 2, 15] (* Harvey P. Dale, Aug 09 2021 *)
PROG
(PARI) s(n) = if(n<2, n=2, sigma(s(n-1))*numdiv(s(n-1))); for(n=1, 20, print(s(n)))
(PARI) { for (n=1, 40, if (n>1, a=sigma(a)*numdiv(a), a=2); write("b063744.txt", n, " ", a) ) } \\ Harry J. Smith, Aug 29 2009
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Aug 14 2001
STATUS
approved