OFFSET
1,5
FORMULA
G.f.: A(x,y) = -(sqrt((2*sqrt(-4*x^2*y+x^2-2*x+1)+3*x-2)/(4*x))-1/2).
EXAMPLE
1,
1, 1,
1, 3, 2,
1, 6, 8, 5,
1,10, 22, 26, 14,
1,15, 50, 85, 90, 42,
1,21,100,225,348,322,132
MATHEMATICA
Table[Binomial[n - 1, n - m] Sum[Binomial[2 k - 2, k - 1] Binomial[n - m, m - k]/m, {k, n}], {n, 10}, {m, n}] // Flatten (* Michael De Vlieger, Oct 05 2020 *)
PROG
(Maxima)
T(n, m):=(binomial(n-1, n-m)*sum(binomial(2*k-2, k-1)*binomial(n-m, m-k), k, 1, n))/m;
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Vladimir Kruchinin, Oct 05 2020
STATUS
approved