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A155866
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A 'Morgan Voyce' transform of the Bell numbers A000110.
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1
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1, 2, 6, 22, 91, 413, 2032, 10754, 60832, 365815, 2327835, 15612872, 109992442, 811500784, 6253327841, 50211976959, 419239644142, 3632891419054, 32616077413970, 302915722319509, 2906047810600157, 28761123170398258
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OFFSET
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0,2
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COMMENTS
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Image of Bell numbers under Riordan array (1/(1-x), x/(1-x)^2).
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LINKS
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FORMULA
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G.f.: 1/(1 -x -x/(1 -x -x/(1 -x -x/(1 -x -2*x/(1 -x -x/(1 -x -3*x/(1 -x -x/(1 -x -4*x/(1 - ... (continued fraction).
a(n) = Sum_{k=0..n} binomial(n+k,2k)*A000110(k).
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MATHEMATICA
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A155866[n_]:= Sum[Binomial[n+j, 2*j]*BellB[j], {j, 0, n}];
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PROG
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(Magma) [(&+[Binomial(n+j, 2*j)*Bell(j): j in [0..n]]): n in [0..30]]; // G. C. Greubel, Jun 10 2021
(Sage)
def A155866(n): return sum( binomial(n+j, 2*j)*bell_number(j) for j in (0..n) )
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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