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A255606
Integer part of the area of a hexagon with side length n.
2
2, 10, 23, 41, 64, 93, 127, 166, 210, 259, 314, 374, 439, 509, 584, 665, 750, 841, 937, 1039, 1145, 1257, 1374, 1496, 1623, 1756, 1893, 2036, 2184, 2338, 2496, 2660, 2829, 3003, 3182, 3367, 3556, 3751, 3951, 4156, 4367, 4583, 4803, 5029, 5261, 5497, 5739, 5985, 6237, 6495
OFFSET
1,1
COMMENTS
Column 4 of A255604.
FORMULA
a(n) = floor(6*n^2/(4*tan(Pi/6))), n >= 1.
MATHEMATICA
Table[IntegerPart[(6*n^2/(4*Tan[Pi/6]))], {n, 50}] (* Michael De Vlieger, Mar 18 2015 *)
PROG
(PARI){for(n=1, 100, a=floor(6*n^2/(4*tan(Pi/6))); print1(a, ", "))}
(PARI) a(n) = sqrtint(27*n^4)>>1; \\ Kevin Ryde, May 07 2021
CROSSREFS
Sequence in context: A120548 A284360 A372846 * A293403 A316451 A120845
KEYWORD
nonn
AUTHOR
Kival Ngaokrajang, Feb 27 2015
STATUS
approved