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A049392
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Expansion of (1-25*x)^(2/5).
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2
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1, -10, -75, -1000, -16250, -292500, -5606250, -112125000, -2312578125, -48821093750, -1049653515625, -22901531250000, -505742148437500, -11281940234375000, -253843655273437500, -5753789519531250000
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: (1-25*x)^(2/5).
a(n) = (5^n/n!) * Product_{k=0..n-1} (5*k-2).
a(n) ~ -2/5*Gamma(3/5)^-1*n^(-7/5)*5^(2*n)*{1 + 7/25*n^-1 + ...}. - Joe Keane (jgk(AT)jgk.org), Nov 24 2001
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EXAMPLE
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(1-x)^(2/5) = 1 - 2/5*x - 3/25*x^2 - 8/125*x^3 - ...
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PROG
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(PARI) first(n) = x='x+O('x^n); Vec((1-25*x)^(2/5)) \\ Iain Fox, Aug 10 2018
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CROSSREFS
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KEYWORD
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sign,easy
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AUTHOR
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Joe Keane (jgk(AT)jgk.org)
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EXTENSIONS
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STATUS
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approved
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