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A001823 Central factorial numbers: column 2 in triangle A008956.
(Formerly M4671 N1998)
5
0, 9, 259, 1974, 8778, 28743, 77077, 179452, 375972, 725781, 1312311, 2249170, 3686670, 5818995, 8892009, 13211704, 19153288, 27170913, 37808043, 51708462, 69627922, 92446431, 121181181, 157000116, 201236140, 255401965, 321205599, 400566474, 495632214 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
REFERENCES
J. Riordan, Combinatorial Identities, Wiley, 1968, p. 217.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Simon Plouffe, Approximations de séries génératrices et quelques conjectures, Dissertation, Université du Québec à Montréal, 1992; arXiv:0911.4975 [math.NT], 2009.
Simon Plouffe, 1031 Generating Functions, Appendix to Thesis, Montreal, 1992
FORMULA
a(n) = n*(n-1)*(2*n+1)*(2*n-1)*(2*n-3)*(10*n+7)/90.
If we replace n with n-1/2 in this formula we get 16*A000586(n).
G.f.: z*(9+196*z+350*z**2+84*z**3+z**4)/(1-z)^7.
a(1)=0, a(2)=9, a(3)=259, a(4)=1974, a(5)=8778, a(6)=28743, a(7)=77077, a(n)=7*a(n-1)-21*a(n-2)+35*a(n-3)-35*a(n-4)+21*a(n-5)-7*a(n-6)+a(n-7). - Harvey P. Dale, Jun 09 2013
MAPLE
A001823:=-(9+196*z+350*z**2+84*z**3+z**4)/(z-1)**7; # conjectured (correctly) by Simon Plouffe in his 1992 dissertation
MATHEMATICA
Table[1/90*n*(n - 1)*(2*n + 1)*(2*n - 1)*(2*n - 3)*(10*n + 7), {n, 40}] (* Stefan Steinerberger, Apr 15 2006 *)
LinearRecurrence[{7, -21, 35, -35, 21, -7, 1}, {0, 9, 259, 1974, 8778, 28743, 77077}, 30] (* Harvey P. Dale, Jun 09 2013 *)
CROSSREFS
A bisection of A181888.
Column 2 in triangle A008956.
Sequence in context: A160073 A157575 A072158 * A229259 A117796 A117051
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Stefan Steinerberger, Apr 15 2006
STATUS
approved

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Last modified April 19 23:40 EDT 2024. Contains 371798 sequences. (Running on oeis4.)