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A065961 a(n) = (3*n - 1)!*n/2. 2
1, 120, 60480, 79833600, 217945728000, 1067062284288000, 8515157028618240000, 103408066955539906560000, 1814811575069725360128000000, 44208809968698509772718080000000, 1447219603135314415919699066880000000, 61998887798316869577999908025139200000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..60

FORMULA

a(n) = (3*n)! / 6.

a(n) - 3*n*(3*n-1)*(3*n-2)*a(n-1) = 0. - R. J. Mathar, Oct 31 2015

PROG

(PARI) { for (n=1, 60, a=(3*n - 1)!*n/2; write("b065961.txt", n, " ", a) ) } \\ Harry J. Smith, Nov 04 2009

(MAGMA) [ Factorial(3*n)/6: n in [1..62] ]; // Vincenzo Librandi, Apr 24 2011

CROSSREFS

Sequence in context: A109897 A301393 A074653 * A333043 A058528 A001421

Adjacent sequences:  A065958 A065959 A065960 * A065962 A065963 A065964

KEYWORD

nonn

AUTHOR

Len Smiley and George E. Antoniou, Dec 08 2001

STATUS

approved

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Last modified May 14 09:34 EDT 2021. Contains 343879 sequences. (Running on oeis4.)