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A247179
Floor of area enclosed in the interior of n unit circles arranged in a circle.
1
0, 0, 2, 4, 6, 9, 13, 18, 23, 29, 35, 42, 50, 58, 67, 76, 87, 98, 109, 121, 134, 147, 161, 176, 191, 207, 224, 241, 259, 277, 296, 316, 337, 358, 379, 402, 424, 448, 472, 497, 523, 549, 575, 603, 631, 660, 689, 719, 749, 781, 812, 845, 878, 912, 946, 981, 1017, 1053, 1090
OFFSET
3,3
COMMENTS
See illustration in links.
FORMULA
a(n) = Floor((n/tan(Pi/n)) - Pi*((n/2)-1)).
PROG
(PARI)for (n=3, 100, print1(floor((n/tan(Pi/n))-Pi*((n/2)-1)), ", "))
CROSSREFS
Sequence in context: A294860 A183920 A079717 * A319158 A175780 A114830
KEYWORD
nonn
AUTHOR
Kival Ngaokrajang, Nov 22 2014
STATUS
approved