OFFSET
1,2
LINKS
Michael De Vlieger, Table of n, a(n) for n = 1..419
MATHEMATICA
Array[Product[DivisorSigma[1, i], {i, #}]*Sum[1/DivisorSigma[1, j], {j, #}] &, 21] (* Michael De Vlieger, Jul 16 2022 *)
PROG
(PARI) a(n) = prod(i=1, n, sigma(i)) * sum(i=1, n, 1/sigma(i)); \\ Michel Marcus, Jan 09 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 30 2002
EXTENSIONS
More terms from Michel Marcus, Jan 09 2021
STATUS
approved