|
Search: id:A064837
|
|
|
| A064837 |
|
a(n)= ( 6*n^4 +30*n^3 -20*n^2 +14 )*n/30 +(n mod 2). |
|
+0
2
|
|
| 0, 2, 18, 114, 420, 1170, 2710, 5538, 10312, 17890, 29338, 45970, 69356, 101362, 144158, 200258, 272528, 364226, 479010, 620978, 794676, 1005138, 1257894, 1559010, 1915096, 2333346, 2821546, 3388114, 4042108, 4793266, 5652014
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
LINKS
|
Harry J. Smith, Table of n, a(n) for n=0,...,500
G. L. Cohen and E. Tonkes, Dartboard arrangements, Elect. J. Combin., 8 (No. 2, 2001), #R4.
|
|
FORMULA
|
a(n)=2*A064838(n). G.f.: 2x*(1-x^5-2x^4+x^3+21x^2+4x)/((1-x)^6*(1+x)). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 05 2008]
|
|
PROGRAM
|
(PARI) { for (n=0, 500, a=(6*n^4 + 30*n^3 - 20*n^2 + 14)*n/30 + n%2; write("b064837.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Sep 28 2009]
|
|
CROSSREFS
|
Sequence in context: A006043 A112328 A038721 this_sequence A027433 A153338 A007798
Adjacent sequences: A064834 A064835 A064836 this_sequence A064838 A064839 A064840
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com), Oct 25 2001
|
|
EXTENSIONS
|
Better description from Frank Ellermann, Mar 16 2002
|
|
|
Search completed in 0.002 seconds
|
