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 A187442 A trisection of A001405 (central binomial coefficients): binomial(3*n,floor(3*n/2)), n>=0. 2
 1, 3, 20, 126, 924, 6435, 48620, 352716, 2704156, 20058300, 155117520, 1166803110, 9075135300, 68923264410, 538257874440, 4116715363800, 32247603683100, 247959266474052, 1946939425648112, 15033633249770520, 118264581564861424 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS For the trisection of sequences see a comment and a reference under A187357. LINKS Table of n, a(n) for n=0..20. FORMULA a(n) = binomial(3*n,floor(3*n/2)), n>=0. O.g.f.: G0(x^2) + 3*x*G2(x^2) with G0(x) and G2(x) the o.g.f.s of A187363 and A187365, respectively. MATHEMATICA Table[Binomial[3n, Floor[(3n)/2]], {n, 0, 20}] (* Harvey P. Dale, Dec 23 2012 *) CROSSREFS A187443 binomial(3*n+1,floor((3*n+1)/2)), A187444 binomial(3*n+2,floor((3*n+2)/2))/2. Sequence in context: A325890 A323563 A228750 * A167590 A228884 A138910 Adjacent sequences: A187439 A187440 A187441 * A187443 A187444 A187445 KEYWORD nonn,easy AUTHOR Wolfdieter Lang, Mar 10 2011 STATUS approved

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Last modified September 9 19:52 EDT 2024. Contains 375765 sequences. (Running on oeis4.)