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A226307 a(n) = Sum_{k >= 0} binomial(6*n,k)*binomial(3*n,k)*binomial(2*n,k). 0
1, 37, 6229, 1454473, 393638933, 115921649662, 36059466046681, 11656478429182365, 3876878952705468437, 1318042625299425997138, 455984891164728575299354, 160005530292143438293125981, 56811170133331347049469683481, 20372514849857567410065222675568, 7367851599324133697992581931476613 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
FORMULA
a(n) ~ 2^(6*n) * 3^(9*n-1) / (Pi^(3/2) * n^(3/2) * 5^(5*n - 1/2)). - Vaclav Kotesovec, Aug 04 2022
MATHEMATICA
Table[Sum[Binomial[6n, k]Binomial[3n, k]Binomial[2n, k], {k, 0, n}], {n, 0, 20}] (* Harvey P. Dale, May 29 2014 *)
CROSSREFS
Sequence in context: A183481 A295415 A202801 * A296598 A221034 A221498
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 07 2013
STATUS
approved

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Last modified April 22 12:13 EDT 2024. Contains 371900 sequences. (Running on oeis4.)