A368612 - OEIS

%I #9 Jan 01 2024 22:28:32

%S 0,0,1,4,8,13,20,27,37,46,56,65,81,92,107,122,140,153,175,190,214,234,

%T 254,271,304,324,347,370,399,418,454,475,509,536,564,591,635,658,689,

%U 719,763,788,835,862,904,945,981,1010,1070,1103,1148,1185,1231,1262,1318,1356

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

%F a(n) = A368610(n) - A092494(n).

%t Table[Sum[PrimePi[k - 1] Ceiling[n/k], {k, 2, n}], {n, 100}]

%Y Cf. A000720 (pi), A046992, A092494, A368610, A368611, A368613.

%K nonn,easy

%O 1,4

%A _Wesley Ivan Hurt_, Dec 31 2023