|
| |
|
|
A140063
|
|
Binomial transform of [1, 3, 7, 0, 0, 0,...].
|
|
2
|
|
|
|
1, 4, 14, 31, 55, 86, 124, 169, 221, 280, 346, 419, 499, 586, 680, 781, 889, 1004, 1126, 1255, 1391, 1534, 1684, 1841, 2005, 2176, 2354, 2539, 2731, 2930, 3136, 3349, 3569, 3796, 4030, 4271, 4519, 4774, 5036
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
Table of n, a(n) for n=1..39.
Derek Kinsella, Plane division by lines and circles
Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
|
|
|
FORMULA
|
A007318 * [1, 3, 7, 0, 0, 0,...].
O.g.f.: x*(1+x+5x^2)/(1-x)^3. - R. J. Mathar, May 06 2008
a(n) = 7*n^2/2-15*n/2+5 = 3*a(n-1)-3*a(n-2)+a(n-3). - R. J. Mathar, Jul 31 2009
a(n)=a(n-1)+7*n-11 (with a(1)=1) [From Vincenzo Librandi, Nov 24 2010]
|
|
|
EXAMPLE
|
a(4) = 31 = (1, 3, 3, 1) dot (1, 3, 7, 0) = (1 + 9 + 21 + 0).
|
|
|
MATHEMATICA
|
s = 1; lst = {s}; Do[s += n + 2; AppendTo[lst, s], {n, 1, 265, 7}]; lst - Zerinvary Lajos, Jul 11 2009
|
|
|
PROG
|
(PARI) a(n)=n*(7*n-15)/2+5 \\ Charles R Greathouse IV, Jun 17 2017
|
|
|
CROSSREFS
|
Sequence in context: A079776 A117109 A317031 * A051409 A072475 A001740
Adjacent sequences: A140060 A140061 A140062 * A140064 A140065 A140066
|
|
|
KEYWORD
|
nonn,easy
|
|
|
AUTHOR
|
Gary W. Adamson, May 03 2008
|
|
|
EXTENSIONS
|
More terms from R. J. Mathar, May 06 2008
|
|
|
STATUS
|
approved
|
| |
|
|
