OFFSET
4,2
REFERENCES
J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 198.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
MATHEMATICA
max = 23; f[x_, y_] := Sum[n!*((x*y)^n/(1 + x*(y-1))^(2*n+1)), {n, 0, max} ]; t = MapIndexed[Take[#1, #2[[1]]]&, CoefficientList[Series[f[x, y], {x, 0, max}, {y, 0, max}], {x, y}]]; a[n_] := t[[n+1, n-3]]; Table[a[n], {n, 4, max}] (* Jean-François Alcover, Feb 08 2016, after Vladeta Jovovic in A058057 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved