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A179572
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Number of permutations of 1..n+5 with the number moved left exceeding the number moved right by n
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1
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146, 392, 960, 2235, 5050, 11198, 24520, 53209, 114674, 245780, 524352, 1114231, 2359482, 4981002, 10486120, 22020565, 46137938, 96469728, 201327488, 419431475, 872416506, 1811940822, 3758098120, 7784630225, 16106129650, 33285999148
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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..99
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FORMULA
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Empirical: a(n)=8*a(n-1)-26*a(n-2)+44*a(n-3)-41*a(n-4)+20*a(n-5)-4*a(n-6) ; G.f.: -x*(-146+776*x-1620*x^2+1677*x^3-868*x^4+180*x^5) / ( (2*x-1)^2*(x-1)^4 ).
Empirical: a(n) = (n+5)*2^(n+4) + (n+5)*(n^2-5*n-42)/6. - R. J. Mathar, May 26 2016
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CROSSREFS
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Sequence in context: A118699 A238579 A238028 * A211838 A158132 A043431
Adjacent sequences: A179569 A179570 A179571 * A179573 A179574 A179575
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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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