OFFSET
0,2
COMMENTS
See A321964 for the definitions.
FORMULA
a(n) ~ 2^(n + 5/2) * n^(n+3) / (3*exp(n)). - Vaclav Kotesovec, Jan 02 2019
MAPLE
A321963List := proc(len) local S, k, m, cf, ser;
S := [seq(k+4, k = 0..len)]: m := 1;
for k from len by -1 to 1 do
m := 1 - S[k]*x/m od;
cf := 1/m:
ser := series(cf, x, len);
seq(coeff(ser, x, n), n = 0..len-1) end:
A321963List(19);
MATHEMATICA
T[n_, k_] := T[n, k] = If[k == n, n + 1, Sum[T[j + k, k] T[n - j, k + 1], {j, 0, n - k - 1}]]; a[n_] := T[n + 2, 2]/3; Table[a[n], {n, 0, 18}] (* Jean-François Alcover, Jul 22 2019, from A127059 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Dec 26 2018
STATUS
approved