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A053129
Binomial coefficients C(2*n-6,7).
7
8, 120, 792, 3432, 11440, 31824, 77520, 170544, 346104, 657800, 1184040, 2035800, 3365856, 5379616, 8347680, 12620256, 18643560, 26978328, 38320568, 53524680, 73629072, 99884400, 133784560, 177100560, 231917400, 300674088, 386206920, 491796152, 621216192
OFFSET
7,1
REFERENCES
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings).
LINKS
M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].
Milan Janjić, Two Enumerative Functions, University of Banja Luka (Bosnia and Herzegovina, 2017).
Ângela Mestre and José Agapito, Square Matrices Generated by Sequences of Riordan Arrays, J. Int. Seq., Vol. 22 (2019), Article 19.8.4.
FORMULA
a(n) = binomial(2*n-6, 7) if n >= 7 else 0.
a(n) = -A053123(n,7), n >= 7; a(n) := 0, n=0..6, (eighth column of shifted Chebyshev's S-triangle, decreasing order).
a(n) = 8*A000973(n).
G.f.: (8+56*x+56*x^2+8*x^3)/(1-x)^8.
a(n) = (n-6)*(n-5)*(n-4)*(n-3)*(2*n-11)*(2*n-9)*(2*n-7)/315. - Wesley Ivan Hurt, Mar 25 2020
From Amiram Eldar, Oct 21 2022: (Start)
Sum_{n>=7} 1/a(n) = 777/5 - 224*log(2).
Sum_{n>=7} (-1)^(n+1)/a(n) = 441/10 - 14*Pi. (End)
MAPLE
A053129:=n->binomial(2*n-6, 7); seq(A053129(n), n=7..50); # Wesley Ivan Hurt, Nov 14 2013
MATHEMATICA
Table[Binomial[2 n - 6, 7], {n, 7, 50}] (* Wesley Ivan Hurt, Nov 14 2013 *)
PROG
(Magma) [Binomial(2*n-6, 7): n in [7..40]]; // Vincenzo Librandi, Oct 07 2011
(PARI) for(n=7, 50, print1(binomial(2*n-6, 7), ", ")) \\ G. C. Greubel, Aug 26 2018
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved