|
| |
|
|
A010973
|
|
Binomial coefficient C(n,20).
|
|
1
| |
|
|
1, 21, 231, 1771, 10626, 53130, 230230, 888030, 3108105, 10015005, 30045015, 84672315, 225792840, 573166440, 1391975640, 3247943160, 7307872110, 15905368710, 33578000610, 68923264410, 137846528820
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 20,2
|
|
|
COMMENTS
| Coordination sequence for 22-dimensional cyclotomic lattice Z[zeta_23].
In this sequence there are no primes - Artur Jasinski (grafix(AT)csl.pl), Dec 02 2007
|
|
|
REFERENCES
| M. Beck and S. Hosten, Cyclotomic polytopes and growth series of cyclotomic lattices, arXiv math.CO/0508136.
|
|
|
LINKS
| Milan Janjic, Two Enumerative Functions
|
|
|
FORMULA
| a(n+19)=n(n+1)(n+2)(n+3)(n+4)(n+5)(n+6)(n+7)(n+8)(n+9)(n+10)(n+11)(n+12)(n+13)(n+14)(n+15)(n+16)(n+17)(n+18)(n+19)/20! - Artur Jasinski (grafix(AT)csl.pl), Dec 02 2007, R. J. Mathar, Jul 07 2009
Gf.: x^20/(1-x)^21. [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Aug 04 2008, R. J. Mathar, Jul 07 2009]
a(n) = n/(n-20) * a(n-1), n>20. - Vincenzo Librandi, Mar 26 2011
|
|
|
MAPLE
| (Maple) seq(binomial(n, 20), n=20..40); # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Aug 04 2008]
|
|
|
MATHEMATICA
| Table[Binomial[n, 20], {n, 20, 50}] (* From Vladimir Joseph Stephan Orlovsky, Apr 22 2011 *)
|
|
|
PROG
| (MAGMA) [ Binomial(n, 20): n in [20..80]]; - Vincenzo Librandi, Mar 26 2011
|
|
|
CROSSREFS
| Pascal's triangle A007318 diagonal [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Aug 04 2008]
Sequence in context: A064322 A126902 A162646 * A022586 A125409 A161581
Adjacent sequences: A010970 A010971 A010972 * A010974 A010975 A010976
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
EXTENSIONS
| Some formulas adjusted to the offset by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 07 2009
|
| |
|
|
