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 A024176 a(n) = (n+2)!(1/3 - 1/4 + ... + c/(n+2)), where c=(-1)^(n+1). 2
 2, 2, 34, 84, 1308, 5424, 89136, 528480, 9442080, 73388160, 1433047680, 13835646720, 294712992000, 3407733504000, 78854259456000, 1063689242112000, 26612469305856000, 410604285708288000, 11055592008050688000, 192132082005405696000, 5543038613901938688000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..100 FORMULA a(n) = 2*A024188(n). a(n) ~ sqrt(2*Pi) * (log(2) - 1/2) * n^(n + 5/2) / exp(n). - Vaclav Kotesovec, Jan 02 2020 MATHEMATICA Table[(n+2)! * Sum[(-1)^(k+1)/k, {k, 3, n+2}], {n, 1, 25}] (* Vaclav Kotesovec, Jan 02 2020 *) PROG (PARI) a(n) = (n+2)!*sum(x=1, n, (-1)^(x+1)/(x+2)); \\ Michel Marcus, Mar 21 2013 CROSSREFS Cf. A024188. Sequence in context: A018976 A074127 A297795 * A349033 A334470 A286375 Adjacent sequences: A024173 A024174 A024175 * A024177 A024178 A024179 KEYWORD nonn AUTHOR Clark Kimberling EXTENSIONS Terms a(13) and beyond from Andrew Howroyd, Jan 01 2020 STATUS approved

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Last modified September 28 01:19 EDT 2023. Contains 365714 sequences. (Running on oeis4.)