|
Search: id:A077588
|
|
|
| A077588 |
|
Maximum number of regions the plane is divided into by n triangles. |
|
+0 4
|
|
| 1, 2, 8, 20, 38, 62, 92, 128, 170, 218, 272, 332, 398, 470, 548, 632, 722, 818, 920, 1028, 1142, 1262, 1388, 1520, 1658, 1802, 1952, 2108, 2270, 2438, 2612, 2792, 2978, 3170, 3368, 3572, 3782, 3998, 4220, 4448, 4682, 4922, 5168, 5420, 5678, 5942, 6212
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
a(n) = A096777(3*n-1) for n>0. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Dec 29 2007
|
|
FORMULA
|
a(n) = 3n^2 - 3n + 2 except when n = 0.
Nearest integer to sum(k>=n, 1/k^2)/sum(k>=n, 1/k^4) - Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 12 2003
|
|
EXAMPLE
|
a(2) = 8 because a Jewish star has 6 points, an interior hexagon and the exterior.
|
|
CROSSREFS
|
Cf. A077591.
Sequence in context: A031114 A130238 A038460 this_sequence A025219 A032767 A032633
Adjacent sequences: A077585 A077586 A077587 this_sequence A077589 A077590 A077591
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Joshua Zucker and the Castilleja School mathcounts club (joshua.zucker(AT)stanfordalumni.org), Nov 07 2002
|
|
|
Search completed in 0.002 seconds
|