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A035017
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One quarter of 9-factorial numbers.
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13
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1, 13, 286, 8866, 354640, 17377360, 1007886880, 67528420960, 5132159992960, 436233599401600, 41005958343750400, 4223613709406291200, 473044735453504614400, 57238412989874058342400
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Index entries for sequences related to factorial numbers
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FORMULA
| 4*a(n) = (9*n-5)(!^9) := product(9*j-5, j=1..n); E.g.f. (-1+(1-9*x)^(-4/9))/4.
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MATHEMATICA
| s=1; lst={s}; Do[s+=n*s; AppendTo[lst, s], {n, 12, 2*5!, 9}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Nov 08 2008]
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CROSSREFS
| Cf. A007559, A034171, A045756, A035012, A035013, A035017, A035018, A035020-A035023.
Sequence in context: A012570 A160294 A092145 * A064750 A023357 A165218
Adjacent sequences: A035014 A035015 A035016 * A035018 A035019 A035020
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KEYWORD
| easy,nonn
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AUTHOR
| Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de)
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