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A039646
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Third column of Jabotinsky-triangle A038455 related to A006963.
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3
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1, 18, 335, 7155, 176554, 4985316, 159168428, 5681708100, 224518859136, 9737714177928, 460132506980640, 23537198603711520, 1296157111841533824, 76467514565810332800, 4812260962479036076800, 321826321845522830649600
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OFFSET
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0,2
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COMMENTS
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Explicit formula for a(n-3) using partitions of n into 3 parts: cf. Knuth's paper for f(n,3) n >= 3, formula with f(k) := A006963(k+1) = (2*k-1)!/k!, k >= 1.
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LINKS
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FORMULA
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MATHEMATICA
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Drop[With[{nmax = 43}, CoefficientList[Series[Log[(1 - Sqrt[1 - 4*x])/x/2]^3/6, {x, 0, nmax}], x]*Range[0, nmax]!], 3] (* G. C. Greubel, dec 14 2017 *)
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PROG
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(PARI) x='x+O('x^30); Vec(serlaplace(log((1-sqrt(1-4*x))/x/2)^3/6)) \\ G. C. Greubel, Dec 14 2017
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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