|
| |
|
|
A016766
|
|
a(n) = (3*n)^2.
|
|
18
|
|
|
|
0, 9, 36, 81, 144, 225, 324, 441, 576, 729, 900, 1089, 1296, 1521, 1764, 2025, 2304, 2601, 2916, 3249, 3600, 3969, 4356, 4761, 5184, 5625, 6084, 6561, 7056, 7569, 8100, 8649, 9216, 9801, 10404, 11025, 11664, 12321, 12996, 13689, 14400, 15129, 15876
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,2
|
|
|
COMMENTS
|
Number of edges of the complete tripartite graph of order 6n, K_n, n, 4n. - Roberto E. Martinez II, Jan 07 2002
Area of a square with side 3n. - Wesley Ivan Hurt, Sep 24 2014
|
|
|
LINKS
|
Ivan Panchenko, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
|
|
|
FORMULA
|
a(n) = 9*n^2 = 9 * A000290(n). - Omar E. Pol, Dec 11 2008
a(n) = 3 * A033428(n). - Omar E. Pol, Dec 13 2008
a(n) = a(n-1) + 9*(2*n-1) for n>0, a(0)=0. - Vincenzo Librandi, Nov 19 2010
From Wesley Ivan Hurt, Sep 24 2014: (Start)
G.f.: 9*x*(1 + x)/(1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3), n>3.
a(n) = A000290(A008585(n)). (End)
|
|
|
MAPLE
|
A016766:=n->(3*n)^2: seq(A016766(n), n=0..50); # Wesley Ivan Hurt, Sep 24 2014
|
|
|
MATHEMATICA
|
(3Range[0, 49])^2 (* Alonso del Arte, Sep 24 2014 *)
|
|
|
PROG
|
(Maxima) A016766(n):=(3*n)^2$
makelist(A016766(n), n, 0, 20); /* Martin Ettl, Nov 12 2012 */
(MAGMA) [(3*n)^2 : n in [0..50]]; // Wesley Ivan Hurt, Sep 24 2014
(PARI) a(n)=9*n^2 \\ Charles R Greathouse IV, Sep 28 2015
|
|
|
CROSSREFS
|
Numbers of the form 9n^2 + kn, for integer n: this sequence (k = 0), A132355 (k = 2), A185039 (k = 4), A057780 (k = 6), A218864 (k = 8). - Jason Kimberley, Nov 09 2012
Sequence in context: A077115 A297584 A073946 * A242538 A083353 A083014
Adjacent sequences: A016763 A016764 A016765 * A016767 A016768 A016769
|
|
|
KEYWORD
|
nonn,easy
|
|
|
AUTHOR
|
N. J. A. Sloane.
|
|
|
EXTENSIONS
|
More terms from Zerinvary Lajos, May 30 2006
|
|
|
STATUS
|
approved
|
| |
|
|
