OFFSET
1,2
EXAMPLE
a(6) = 12 = (1 + 1 + 1 + 2 + 1 + 6), where pod(n)/ n = 1, 1, 1, 2, 1, 6, 1, 8, 3, 10, 1, 144, ...
MATHEMATICA
popd[n_] := n^(DivisorSigma[0, n]/2 - 1); Accumulate @ Array[popd, 44] (* Amiram Eldar, Nov 30 2020 *)
PROG
(Magma) [&+[&*Divisors(k) / k: k in [1..n]]: n in [1..100]]
(PARI) a(n) = sum(k=1, n, vecprod(divisors(k))/k); \\ Michel Marcus, Nov 30 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Nov 29 2020
STATUS
approved