OFFSET
1,2
PROG
(PARI) f(n) = sum(k=1, n, ceil(numdiv(k)/2)); \\ A094820
a(n) = sum(k=1, n, f(k)); \\ Michel Marcus, Sep 29 2021
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jonathan Vos Post, Apr 24 2010
EXTENSIONS
a(2) corrected by Georg Fischer, Sep 29 2021
STATUS
approved