|
|
A064201
|
|
9 times octagonal numbers: a(n) = 9n(3n-2).
|
|
3
|
|
|
0, 9, 72, 189, 360, 585, 864, 1197, 1584, 2025, 2520, 3069, 3672, 4329, 5040, 5805, 6624, 7497, 8424, 9405, 10440, 11529, 12672, 13869, 15120, 16425, 17784, 19197, 20664, 22185, 23760, 25389, 27072, 28809, 30600, 32445, 34344, 36297
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
REFERENCES
|
L. Berzolari, Allgemeine Theorie der Höheren Ebenen Algebraischen Kurven, Encyclopädie der Mathematischen Wissenschaften mit Einschluss ihrer Anwendungen. Band III_2. Heft 3, Leipzig: B. G. Teubner, 1906. p. 341.
|
|
LINKS
|
|
|
FORMULA
|
a(n) = 9*(n-2)*(3*n-8), with offset 2.
|
|
MATHEMATICA
|
9*PolygonalNumber[8, Range[0, 40]] (* Requires Mathematica version 10 or later *) (* or *) LinearRecurrence[{3, -3, 1}, {0, 9, 72}, 40] (* Harvey P. Dale, Aug 01 2020 *)
|
|
PROG
|
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
Antreas P. Hatzipolakis (xpolakis(AT)otenet.gr), Sep 22 2001
|
|
EXTENSIONS
|
Better definition, corrected offset and edited from Omar E. Pol, Dec 11 2008
|
|
STATUS
|
approved
|
|
|
|