OFFSET
0,2
FORMULA
G.f.: 2/(1 - 4*x + sqrt(1 - 4*x - 4*x*y) - 4*x*y).
T(n, k) = binomial(n, k)*CatalanNumber(n)*(2*n + 1). - Peter Luschny, Feb 15 2023
EXAMPLE
Triangle T(n, m) starts:
[0] 1;
[1] 3, 3;
[2] 10, 20, 10;
[3] 35, 105, 105, 35;
[4] 126, 504, 756, 504, 126;
[5] 462, 2310, 4620, 4620, 2310, 462;
[6] 1716, 10296, 25740, 34320, 25740, 10296, 1716;
[7] 6435, 45045, 135135, 225225, 225225, 135135, 45045, 6435;
MAPLE
CatalanNumber := n -> binomial(2*n, n)/(n + 1):
T := (n, k) -> (2*n + 1)*CatalanNumber(n)*binomial(n, k):
seq(seq(T(n, k), k = 0..n), n = 0..8); # Peter Luschny, Feb 15 2023
PROG
(Maxima)
T(n, m):=if n<m then 0 else ((n-m+1)*binomial(2*n+1, m)*binomial(2*n-m+2, n-m+1))/(2*n-m+2);
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Vladimir Kruchinin, Feb 15 2023
STATUS
approved