OFFSET
0,2
LINKS
Robert Israel, Table of n, a(n) for n = 0..1145
FORMULA
From Robert Israel, Nov 26 2018: (Start)
Empirical g.f.: (2*x^2-3*x+1)/(2*sqrt(4*x^2-8*x+1)*x)+(x-1)/(2*x).
Empirical recurrence: 8*n*a(n)+(-32-28*n)*a(1+n)+(78+30*n)*a(n+2)+(-45-11*n)*a(n+3)+(5+n)*a(n+4)=0. (End)
MAPLE
T:= proc(n, k) option remember;
if k=0 or k=n then return 1 fi;
if k > n then return 0 fi;
procname(n-1, k-1) + 2*procname(n-2, k-1) + procname(n-1, k)
end proc;
T(2, 1):= 3:
seq(T(2*n+1, n), n=0..30); # Robert Israel, Nov 26 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved