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 A136636 a(n) = n * C(2*3^(n-1), n) for n>=1. 4
 2, 30, 2448, 1265004, 4368213360, 106458751541142, 19173684851378353296, 26413015283743616538733008, 285290979402099025600644272168880, 24601033850235942230699563821233785600080 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Equals column 1 of triangle A136635. LINKS FORMULA a(n) ~ 2^n * 3^(n*(n-1)) / (n-1)!. - Vaclav Kotesovec, Jul 02 2016 MAPLE A136636:=n->n*binomial(2*3^(n-1), n); seq(A136636(n), n=1..10); # Wesley Ivan Hurt, Apr 29 2014 MATHEMATICA Table[n*Binomial[2*3^(n - 1), n], {n, 10}] (* Wesley Ivan Hurt, Apr 29 2014 *) PROG (PARI) {a(n)=n*binomial(2*3^(n-1), n)} CROSSREFS Cf. A136635 (triangle), A014070 (main diagonal), A136393 (column 0), A136637 (row sums), A136638 (antidiagonal sums). Sequence in context: A158260 A099800 A099929 * A220719 A030249 A000187 Adjacent sequences:  A136633 A136634 A136635 * A136637 A136638 A136639 KEYWORD nonn,easy AUTHOR Vladeta Jovovic and Paul D. Hanna, Jan 15 2008 STATUS approved

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Last modified July 5 11:09 EDT 2022. Contains 355097 sequences. (Running on oeis4.)