OFFSET
1,2
EXAMPLE
a(3) = d(1)*d(3)*d(5) = 1*2*2 = 4.
MATHEMATICA
Rest @ FoldList[Times, 1, DivisorSigma[0, Range[1, 50, 2]]] (* Amiram Eldar, May 10 2020 *)
PROG
(PARI) a(n) = prod(k=1, n, numdiv(2*k-1)); \\ Michel Marcus, May 10 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Ctibor O. Zizka, May 10 2020
STATUS
approved