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A179573
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Number of permutations of 1..n+6 with the number moved left exceeding the number moved right by n
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1
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1289, 4859, 16615, 53830, 168994, 520598, 1585390, 4794375, 14437999, 43373253, 130121945, 390106124, 1169206896, 3504084520, 10502294920, 31480673141, 94375961733, 282966406751, 848513346011, 2544634069346, 7631805056014
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OFFSET
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1,1
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COMMENTS
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Recurrence would also extend to an a(0) if the definition were made to exclude the identity permutation
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LINKS
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R. H. Hardin, Table of n, a(n) for n=1..45
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FORMULA
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Empirical: a(n)=14*a(n-1)-85*a(n-2)+294*a(n-3)-639*a(n-4)+906*a(n-5)-839*a(n-6)+490*a(n-7)-164*a(n-8)+24*a(n-9) ; G.f.: -x*(1289-13187*x+58154*x^2-144731*x^3+222774*x^4-217511*x^5+131690*x^6-45220*x^7+6744*x^8) / ( (-1+3*x)*(2*x-1)^3*(x-1)^5 ).
Empirical: a(n) = 3^(n+6) +(n+6)*(n^3-12*n^2-133*n-192)/24 +(n^2-n-50)*2^(n+3). - R. J. Mathar, May 26 2016
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CROSSREFS
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Sequence in context: A140914 A239436 A239939 * A264243 A020401 A106816
Adjacent sequences: A179570 A179571 A179572 * A179574 A179575 A179576
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, g.f. from R. J. Mathar in the Sequence Fans Mailing List, Jul 19 2010
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STATUS
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approved
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