A368610 a(n) = Sum_{k=1..n} pi(k) * ceiling(n/k).

0, 1, 4, 8, 14, 20, 30, 38, 49, 59, 72, 82, 101, 113, 130, 147, 167, 181, 206, 222, 248, 270, 293, 311, 346, 367, 392, 416, 448, 468, 508, 530, 565, 594, 624, 653, 700, 724, 757, 789, 836, 862, 913, 941, 985, 1028, 1067, 1097, 1159, 1193, 1240, 1279, 1328, 1360, 1418

Offset: 1

Author

Wesley Ivan Hurt, Dec 31 2023

Keywords

• nonn
• easy

Crossrefs

Cf. A000720 (pi), A046992, A092494, A368611, A368612, A368613.

Programs

Mathematica

Table[Sum[PrimePi[k] Ceiling[n/k], {k, n}], {n, 100}]

Formula

a(n) = A092494(n) + A368612(n).