A228189 Volume of right circular cone (rounded down) with the diameter of base and height equal to n.

0, 2, 7, 16, 32, 56, 89, 134, 190, 261, 348, 452, 575, 718, 883, 1072, 1286, 1526, 1795, 2094, 2424, 2787, 3185, 3619, 4090, 4601, 5152, 5747, 6385, 7068, 7799, 8578, 9408, 10289, 11224, 12214, 13260, 14365, 15529, 16755, 18043, 19396, 20814, 22301, 23856, 25482

Offset: 1

Author

K. D. Bajpai, Aug 17 2013

Keywords

• nonn
• easy

Examples

			a(3) = 7 because volume = ((Pi*n^2)/4)*(n/3) = ((Pi*3*3)/4)*(3/3) = 7.06858 and floor(7.06858) = 7.
		

Links

• Georg Fischer, Table of n, a(n) for n = 1..1000 [first 574 terms from _K. D. Bajpai_]

Programs

Maple

a:= n-> floor((Pi*n^3)/12):
seq(a(n), n=1..48);

Mathematica

Table[Floor[(Pi n^3)/12],{n,50}] (* Harvey P. Dale, May 25 2019 *)

PARI

a(n)=Pi*n^3\12 \\ Charles R Greathouse IV, Aug 25 2014

Formula

a(n) = floor((Pi*n^3)/12).