A027394 Number of labeled servers of dimension 7.

1, 7, 70, 854, 12068, 191996, 3374392, 64635640, 1335753664, 29548086848, 695221579136, 17307703505792, 453917707384960, 12494500081323904, 359807967643449088, 10809816056831434496, 337981832271282386432

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

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..7 ) ).

Mathematica

Table[n!*SeriesCoefficient[E^(Sum[((1 + x)^i - 1)/i, {i, 1, 7}]), {x, 0, n}], {n, 0, 20}] (* Vincenzo Librandi, Dec 31 2012 *)

Crossrefs

Sequence in context: A228927 A097184 A002296 * A346767 A209327 A255519

Adjacent sequences: A027391 A027392 A027393 * A027395 A027396 A027397

Keyword

nonn

Author

Olivier Gérard

Status

approved