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 A065180 Number of site swap patterns with 4 balls and exact period n. 5
 1, 4, 20, 90, 420, 1910, 8820, 40590, 187880, 871494, 4057620, 18945960, 88738020, 416787030, 1962922276, 9268287390, 43868210820, 208109782580, 989400443220, 4713395564772, 22497100553820, 107572434560790, 515241748300020 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS G. C. Greubel, Table of n, a(n) for n = 1..1000 Juggling Information Service, Site Swap FAQs MAPLE [seq(DistSS(p, 4), p=1..60)]; A065180 := proc(n)     add( mobius(n/d)*(5^d-4^d), d=numtheory[divisors](n)) /n ; end proc: seq(A065180(n), n=1..30) ; # R. J. Mathar, Aug 05 2015 MATHEMATICA a[n_] := DivisorSum[n, MoebiusMu[n/#]*(5^# - 4^#)&]/n; Array[a, 25] (* Jean-François Alcover, Mar 06 2016 *) CROSSREFS Row 4 of A065177. Cf. A065178, A065179. Sequence in context: A017964 A017965 A180284 * A229245 A328153 A070733 Adjacent sequences:  A065177 A065178 A065179 * A065181 A065182 A065183 KEYWORD nonn AUTHOR Antti Karttunen, Oct 19 2001 STATUS approved

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Last modified December 13 06:26 EST 2019. Contains 329968 sequences. (Running on oeis4.)