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A228391 Volume of elliptic cone (rounded down) with semi-minor axis = height = n and semi-major axis = 3*n/2. 2
1, 12, 42, 100, 196, 339, 538, 804, 1145, 1570, 2090, 2714, 3451, 4310, 5301, 6433, 7717, 9160, 10774, 12566, 14547, 16725, 19111, 21714, 24543, 27608, 30917, 34482, 38310, 42411, 46795, 51471, 56449, 61738, 67347, 73287, 79565, 86192, 93178, 100530, 108260, 116377 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..5000

FORMULA

a(n) = floor(Pi*n^3/2).

EXAMPLE

a(9) = 1145 since volume = ((Pi*n*1.5*n)*(n)/3) = ((Pi*9*1.5*9)*(9)/3) = 1145.110522 and floor(1145.110522) = 1145.

MAPLE

KD := proc() local a; a:= floor(((Pi*n*1.5*n)*(n)/3));

RETURN (a):

end:

seq(KD(), n=1..100);

CROSSREFS

Cf. A228189 (similar sequence for right circular cone).

Sequence in context: A009948 A193068 A007586 * A122973 A074356 A172294

Adjacent sequences:  A228388 A228389 A228390 * A228392 A228393 A228394

KEYWORD

nonn

AUTHOR

K. D. Bajpai, Aug 21 2013

STATUS

approved

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Last modified November 15 15:59 EST 2018. Contains 317239 sequences. (Running on oeis4.)