OFFSET
1,2
LINKS
J.-C. Novelli and J.-Y. Thibon, Hopf algebras and dendriform structures arising from parking functions, arXiv:math/0511200 [math.CO], 2005.
FORMULA
G.f.: 1 - Product_{i>=1} (1-t^i)^c(i), where c(i) is the number of connected parking functions of length i.
MATHEMATICA
terms = 18;
s = (1 - 1/(1 + Sum[(n+1)^(n-1)*t^n, {n, 1, terms+1}]))/t + O[t]^(terms+1);
cc = CoefficientList[s, t];
gf = Product[(1 - t^i)^cc[[i]], {i, 1, terms+1}] + O[t]^(terms+1);
CoefficientList[gf, t] // Abs // Rest (* Jean-François Alcover, Feb 17 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jean-Yves Thibon (jyt(AT)univ-mlv.fr), Oct 22 2006, Oct 24 2006
STATUS
approved