OFFSET
1,4
FORMULA
MATHEMATICA
Table[Sum[(n - i)*(PrimePi[i] - PrimePi[i - 1]) (1 - Ceiling[n/i] + Floor[n/i]), {i, n}], {n, 80}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Sep 09 2020
STATUS
approved