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A027400
Number of labeled servers of dimension 13.
1
1, 13, 247, 5811, 159939, 4993911, 173345913, 6593244957, 271829934441, 12046090972149, 569908578269511, 28625770524756483, 1519419921487859547, 84887883112007162511, 4974828151748224390569, 304918429757614547396301
OFFSET
0,2
LINKS
R. Donaghey, Binomial self-inverse sequences and tangent coefficients, J. Combin. Theory, Series A, 21 (1976), 155-163.
FORMULA
E.g.f.: exp( sum( ((1+x)^i-1)/i, i=1..13 ) ).
MATHEMATICA
Table[n!*SeriesCoefficient[E^(Sum[((1+x)^i - 1)/i, {i, 1, 13}]), {x, 0, n}], {n, 0, 20}] (* Vincenzo Librandi, Dec 31 2012 *)
CROSSREFS
Sequence in context: A203156 A049665 A196665 * A053100 A320308 A219059
KEYWORD
nonn
STATUS
approved