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A014318
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Convolution of Catalan numbers and powers of 2.
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11
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1, 3, 8, 21, 56, 154, 440, 1309, 4048, 12958, 42712, 144210, 496432, 1735764, 6145968, 21986781, 79331232, 288307254, 1054253208, 3875769606, 14315659632, 53097586284, 197677736208, 738415086066
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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G.f.: (1-sqrt(1-4*z))/(2*z*(1-2*z)).
a(n) = Sum_{j=0..n} (2^(n-j) * binomial(2*j,j)/(j+1)). (End)
Recurrence: (n+1)*a(n) = 32*(2*n-7)*a(n-5) + 48*(8-3*n)*a(n-4) + 8*(16*n-29)*a(n-3) + 4*(13-14*n)*a(n-2) + 12*n*a(n-1), n>=5. - Fung Lam, Mar 09 2014
Asymptotics: a(n) ~ 2^(2n+1)/n^(3/2)/sqrt(Pi). - Fung Lam, Mar 21 2014
G.f. A(x) satisfies: A(x) = 1 / (1 - 2*x) + x * (1 - 2*x) * A(x)^2. - Ilya Gutkovskiy, Nov 21 2021
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MAPLE
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a:=proc(n) options operator, arrow: sum(2^(n-j)*binomial(2*j, j)/(j+1), j=0..n) end proc: seq(a(n), n=0..23); # Emeric Deutsch, Oct 16 2008
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MATHEMATICA
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a[n_]:= a[n]= Sum[2^(n-j)*CatalanNumber[j], {j, 0, n}];
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PROG
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(Magma)
A014318:= func< n | (&+[2^(n-j)*Catalan(j): j in [0..n]]) >;
(SageMath)
def A014318(n): return sum(2^(n-j)*catalan_number(j) for j in range(n+1))
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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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