|
|
A026764
|
|
a(n) = T(n, floor(n/2)), T given by A026758.
|
|
10
|
|
|
1, 1, 2, 4, 7, 16, 27, 66, 109, 279, 453, 1201, 1922, 5242, 8284, 23133, 36155, 103015, 159435, 462269, 709246, 2088146, 3178992, 9487405, 14343567, 43328580, 65099245, 198798447, 297015765, 915950385, 1361584755, 4236322720
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
MAPLE
|
T:= proc(n, k) option remember;
if n<0 then 0;
elif k=0 or k = n then 1;
elif type(n, 'odd') and k <= (n-1)/2 then
procname(n-1, k-1)+procname(n-2, k-1)+procname(n-1, k) ;
else
procname(n-1, k-1)+procname(n-1, k) ;
end if ;
end proc;
|
|
MATHEMATICA
|
T[n_, k_]:= T[n, k]= If[n<0, 0, If[k==0 || k==n, 1, If[OddQ[n] && k<=(n - 1)/2, T[n-1, k-1] + T[n-2, k-1] + T[n-1, k], T[n-1, k-1] + T[n-1, k] ]] ]; Table[T[n, Floor[n/2]], {n, 0, 30}] (* G. C. Greubel, Oct 31 2019 *)
|
|
PROG
|
(Sage)
@CachedFunction
def T(n, k):
if (n<0): return 0
elif (k==0 or k==n): return 1
elif (mod(n, 2)==1 and k<=(n-1)/2): return T(n-1, k-1) + T(n-2, k-1) + T(n-1, k)
else: return T(n-1, k-1) + T(n-1, k)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|