OFFSET
1,3
COMMENTS
Partial sums of A066328.
LINKS
FORMULA
MAPLE
seq(add(k*floor(n/ithprime(k)), k=1..n), n=1..65); # Paolo P. Lava, May 14 2018
MATHEMATICA
Table[Sum[k Floor[n/Prime[k]], {k, n}], {n, 65}]
nmax = 65; Rest[CoefficientList[Series[1/(1 - x) Sum[k x^Prime[k]/(1 - x^Prime[k]), {k, 1, nmax}], {x, 0, nmax}], x]]
a[n_] := Plus @@ (PrimePi[#[[1]]] & /@ FactorInteger[n]); a[1] = 0; Accumulate[Table[a[n], {n, 65}]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, May 05 2018
STATUS
approved