A186245 a(n) = binomial(n^2, 2*n).

1, 84, 12870, 3268760, 1251677700, 675248872536, 488526937079580, 456703981505085600, 535983370403809682970, 771629762387959506903300, 1337261858854117218288723600, 2746379593275133584459064976784, 6596095888094645606758451183394760

Offset: 2

Author

Alex Ratushnyak, Aug 18 2012

Keywords

• nonn

Links

• Michael De Vlieger, Table of n, a(n) for n = 2..205

Crossrefs

Cf. A014062.

Programs

Mathematica

Array[Binomial[#^2, 2 #] &, 13, 2] (* Michael De Vlieger, May 21 2021 *)

Python

import math
for n in range(2,22):
    x = n*n
    y = n+n
    print(math.factorial(x) / (math.factorial(x-y) * math.factorial(y)), end=',')