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 A138462 A bisection of A006318. 2
 1, 6, 90, 1806, 41586, 1037718, 27297738, 745387038, 20927156706, 600318853926, 17518619320890, 518431875418926, 15521467648875090, 469286147871837366, 14308406109097843626, 439442782615614361662, 13582285614213903189954, 422158527806921249683014 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Colin Barker, Table of n, a(n) for n = 0..300 FORMULA a(n) = Sum_{i=0..2n} (C(2*n+1,i+1)*C(2*n+i,i))/(2*n+1). - Vladimir Kruchinin, Apr 02 2017 PROG (Maxima) a(n):=sum(binomial(2*n+1, i+1)*binomial(2*n+i, i), i, 0, 2*n)/(2*n+1); /* Vladimir Kruchinin, Apr 02 2017 */ (PARI) a(n) = sum(i=0, 2*n, binomial(2*n+1, i+1)*binomial(2*n+i, i))/(2*n+1) \\ Colin Barker, Dec 28 2017 CROSSREFS Sequence in context: A247150 A201073 A006480 * A002896 A266734 A004996 Adjacent sequences:  A138459 A138460 A138461 * A138463 A138464 A138465 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, May 08 2008 STATUS approved

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Last modified April 15 21:48 EDT 2021. Contains 343007 sequences. (Running on oeis4.)