login
A010978
a(n) = binomial(n,25).
3
1, 26, 351, 3276, 23751, 142506, 736281, 3365856, 13884156, 52451256, 183579396, 600805296, 1852482996, 5414950296, 15084504396, 40225345056, 103077446706, 254661927156, 608359048206, 1408831480056, 3169870830126, 6943526580276, 14833897694226, 30957699535776
OFFSET
25,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (26, -325, 2600, -14950, 65780, -230230, 657800, -1562275, 3124550, -5311735, 7726160, -9657700, 10400600, -9657700, 7726160, -5311735, 3124550, -1562275, 657800, -230230, 65780, -14950, 2600, -325, 26, -1).
FORMULA
From Zerinvary Lajos, Aug 18 2008: (Start)
a(n) = C(n,25), n >= 25.
G.f.: x^25/(1-x)^26. (End) [G.f. corrected by Georg Fischer, May 19 2019]
From Amiram Eldar, Dec 11 2020: (Start)
Sum_{n>=25} 1/a(n) = 25/24.
Sum_{n>=25} (-1)^(n+1)/a(n) = A001787(25)*log(2) - A242091(25)/24! = 419430400*log(2) - 155661889015631695/535422888 = 0.9641184185... (End)
MAPLE
seq(binomial(n, 25), n=25..41); # Zerinvary Lajos, Aug 18 2008
MATHEMATICA
Table[Binomial[n, 25], {n, 25, 50}] (* Vladimir Joseph Stephan Orlovsky, Apr 26 2011 *)
PROG
(Magma) [Binomial(n, 25): n in [25..50]]; // Vincenzo Librandi, Jun 12 2013
(PARI) x='x+O('x^50); Vec(x^25/(1-x)^26) \\ G. C. Greubel, Nov 23 2017
CROSSREFS
KEYWORD
nonn,easy
STATUS
approved