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A368641
a(n) = Sum_{k=2..n} pi(k-1) * (ceiling(n/k) - floor(n/k)).
2
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
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}]
KEYWORD
nonn,easy
AUTHOR
Wesley Ivan Hurt, Jan 01 2024
STATUS
approved