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A333644
a(n) = Sum_{k=1..n} floor(n/k) * prime(k).
0
2, 7, 14, 26, 39, 62, 81, 112, 142, 187, 220, 287, 330, 395, 460, 544, 605, 712, 781, 904, 1001, 1116, 1201, 1376, 1486, 1633, 1766, 1945, 2056, 2279, 2408, 2623, 2798, 3001, 3180, 3482, 3641, 3876, 4091, 4406, 4587, 4924, 5117, 5432, 5717, 6004, 6217, 6668, 6914, 7285
OFFSET
1,1
COMMENTS
Partial sums of A007445.
FORMULA
G.f.: (1/(1 - x)) * Sum_{k>=1} prime(k) * x^k / (1 - x^k).
MATHEMATICA
Table[Sum[Floor[n/k] Prime[k], {k, n}], {n, 50}]
PROG
(PARI) a(n) = sum(k=1, n, (n\k)*prime(k)); \\ Michel Marcus, Mar 31 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Mar 31 2020
STATUS
approved