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 A084944 Hendecagorials: n-th polygorial for k=11. 20
 1, 1, 11, 330, 19140, 1818300, 256380300, 50250538800, 13065140088000, 4350691649304000, 1805537034461160000, 913601739437346960000, 553642654099032257760000, 395854497680808064298400000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS G. C. Greubel, Table of n, a(n) for n = 0..220 Daniel Dockery, Polygorials, Special "Factorials" of Polygonal Numbers, preprint, 2003. FORMULA a(n) = polygorial(n, 11) = (A000142(n)/A000079(n))*A084949(n) = (n!/2^n)*Product_{i=0..n-1} (9*i+2) = (n!/2^n)*9^n*Pochhammer(2/9, n) = (n!/2^n)*9^n*GAMMA(n+2/9)/GAMMA(2/9). 2*a(n) = n*(9*n-7)*a(n-1). - R. J. Mathar, Mar 12 2019 MAPLE a := n->n!/2^n*product(9*i+2, i=0..n-1); [seq(a(j), j=0..30)]; MATHEMATICA polygorial[k_, n_] := FullSimplify[ n!/2^n (k -2)^n*Pochhammer[2/(k - 2), n]]; Array[polygorial[11, #] &, 16, 0] (* Robert G. Wilson v, Dec 13 2016 *) CROSSREFS Cf. A006472, A001044, A000680, A084939, A084940, A084941, A084942, A084943, A085356. Sequence in context: A295171 A254545 A160293 * A107441 A086923 A206532 Adjacent sequences:  A084941 A084942 A084943 * A084945 A084946 A084947 KEYWORD easy,nonn AUTHOR Daniel Dockery (peritus(AT)gmail.com), Jun 13 2003 STATUS approved

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Last modified October 20 15:46 EDT 2019. Contains 328267 sequences. (Running on oeis4.)