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 A019577 Place n distinguishable balls in n boxes (in n^n ways); let f(n,k) = number of ways that max in any box is k, for 1<=k<=n; sequence gives f(n,2)/n. 1
 0, 1, 6, 45, 420, 4800, 65520, 1045170, 19126800, 395448480, 9120988800, 232248416400, 6471820555200, 195912193276800, 6402199349145600, 224636583525354000, 8423131243022496000, 336138596955120960000, 14224375944427993344000, 636224790017466730080000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Alois P. Heinz, Table of n, a(n) for n = 1..200 FORMULA Sum n! (n-1)! / ( 2^d (n-2d)! d! d! ), d=1..[ n/2 ]. CROSSREFS Cf. A019576. Sequence in context: A137974 A291421 A001879 * A097814 A239910 A228194 Adjacent sequences:  A019574 A019575 A019576 * A019578 A019579 A019580 KEYWORD nonn,easy AUTHOR Lee Corbin (lcorbin(AT)tsoft.com), N. J. A. Sloane. STATUS approved

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Last modified September 22 12:34 EDT 2020. Contains 337289 sequences. (Running on oeis4.)