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A304940
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Expansion of ((1 + 4*x)/(1 - 4*x))^(1/2).
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2
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1, 4, 8, 32, 96, 384, 1280, 5120, 17920, 71680, 258048, 1032192, 3784704, 15138816, 56229888, 224919552, 843448320, 3373793280, 12745441280, 50981765120, 193730707456, 774922829824, 2958796259328, 11835185037312, 45368209309696, 181472837238784
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OFFSET
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0,2
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COMMENTS
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Let ((1 + k*x)/(1 - k*x))^(m/k) = a(0) + a(1)*x + a(2)*x^2 + ...
Then n*a(n) = 2*m*a(n-1) + k^2*(n-2)*a(n-2) for n > 1.
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LINKS
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FORMULA
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n*a(n) = 4*a(n-1) + 4^2*(n-2)*a(n-2) for n > 1.
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PROG
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(PARI) N=66; x='x+O('x^N); Vec(((1+4*x)/(1-4*x))^(1/2))
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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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