A368641 a(n) = Sum_{k=2..n} pi(k-1) * (ceiling(n/k) - floor(n/k)).

0, 0, 0, 1, 3, 4, 8, 9, 14, 17, 23, 21, 32, 34, 40, 43, 55, 53, 68, 67, 79, 87, 99, 92, 114, 120, 129, 132, 152, 145, 171, 169, 187, 197, 209, 203, 236, 240, 253, 251, 283, 274, 308, 307, 322, 341, 363, 347, 389, 392, 415, 421, 452, 443, 477, 475, 507, 522, 547, 522

Offset

1,5

Links

Table of n, a(n) for n=1..60.

Formula

a(n) = A368612(n) - A368613(n).

a(n) = A368616(n) - A048865(n).

Mathematica

Table[Sum[PrimePi[k - 1] (Ceiling[n/k] - Floor[n/k]), {k, 2, n}], {n, 100}]

Crossrefs

Cf. A000720 (pi), A046992, A048865, A092494, A368610, A368611, A368612, A368613, A368616.

Sequence in context: A306901 A355477 A341578 * A046974 A177986 A186775

Adjacent sequences: A368638 A368639 A368640 * A368642 A368643 A368644

Keyword

nonn,easy

Author

Wesley Ivan Hurt, Jan 01 2024

Status

approved