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 A213168 a(n) = n!/2 - (n-1)! - n + 2. 2
 0, 0, 4, 33, 236, 1795, 15114, 141113, 1451512, 16329591, 199583990, 2634508789, 37362124788, 566658892787, 9153720575986, 156920924159985, 2845499424767984, 54420176498687983, 1094805903679487982, 23112569077678079981, 510909421717094399980 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,3 COMMENTS Row sums of A142706 for k=1..n-1. LINKS Vincenzo Librandi, Table of n, a(n) for n = 2..200 FORMULA a(n) = A001286(n-1) - n + 2. - Anton Zakharov, Sep 08 2016 MATHEMATICA Table[n!/2 - (n - 1)! - n + 2, {n, 2, 20}] PROG (Maxima) A213168(n):=n!/2-(n-1)!-n+2\$ makelist(A213168(n), n, 2, 30); /* Martin Ettl, Nov 03 2012 */ (MAGMA) [Factorial(n)/2-Factorial(n-1)-n+2: n in [2..25]]; // Vincenzo Librandi, Sep 09 2016 CROSSREFS Cf. A001286. Cf. A142706, A051683, A152883. Cf. A200748 (considered as a triangular array). Sequence in context: A131509 A221030 A081007 * A203212 A088317 A041024 Adjacent sequences:  A213165 A213166 A213167 * A213169 A213170 A213171 KEYWORD nonn,easy AUTHOR Olivier Gérard, Nov 02 2012 STATUS approved

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Last modified January 24 16:44 EST 2021. Contains 340411 sequences. (Running on oeis4.)