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A362643
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Number of labeled magmas with n elements satisfying the equations (xy)y = x and x(yz) = xy.
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4
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1, 1, 2, 10, 94, 1636, 49636, 2489824, 204626528, 27296455456, 5930440245856, 2144594499551296, 1333437360189448768, 1510196144261999035648, 3333925936841219018864384, 15357830414682103475484461056, 155003843551785210349182746546176
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OFFSET
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0,3
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LINKS
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FORMULA
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E.g.f.: Sum_{k>=0} log(B(k,x))^k/k! where B(k,x) = Sum_{j>=0} A000085(j)^k*x^j/j!.
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PROG
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(PARI)
B(n, k)=my(p=serlaplace(exp(x + x^2/2 + O(x*x^n)))); sum(j=0, n, polcoef(p, j)^k*x^j/j!, O(x*x^n))
seq(n)=Vec(serlaplace(sum(k=0, n, log(B(n-k+1, k))^k/k!)))
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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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