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 A143217 a(n) = n! * (!(n+1)) = n! * Sum_{k=0..n} k!. 3
 1, 2, 8, 60, 816, 18480, 629280, 29806560, 1864154880, 148459288320, 14652782323200, 1754531527795200, 250496911136102400, 42032247888401971200, 8188505926989625036800, 1832839841629043799552000, 467088574163459753336832000, 134454052266325985991942144000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA a(n) = A000142(n) * A003422(n), where A000142 = the factorials: (1, 1, 2, 6, 24,...) and A003422 = partial sums of the factorials: (1, 2, 4, 10, 34, 154,...) Equals row sums of triangle A143216. EXAMPLE a(4) = 816 = 4! * 34, where 34 = A003422(4) and A000142 = (1, 1, 2, 6, 24, 120,...). a(4) = 816 = sum of row 4 terms of triangle A143216: (24 + 24 + 48 + 144 + 576) MATHEMATICA Table[n!*Sum[i!, {i, 0, n}], {n, 0, 16}] CROSSREFS Cf. A000142(n) * A003422(n). Cf. A143216, A061640, A217238, A217239. Sequence in context: A294331 A036794 A096121 * A192412 A191553 A321979 Adjacent sequences:  A143214 A143215 A143216 * A143218 A143219 A143220 KEYWORD nonn,easy AUTHOR Gary W. Adamson, Jul 30 2008 EXTENSIONS Edited and extended by Olivier Gérard, Sep 28 2012 STATUS approved

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Last modified March 29 17:23 EDT 2020. Contains 333116 sequences. (Running on oeis4.)