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

%I A186245 #19 May 22 2021 04:26:58
%S A186245 1,84,12870,3268760,1251677700,675248872536,488526937079580,
%T A186245 456703981505085600,535983370403809682970,771629762387959506903300,
%U A186245 1337261858854117218288723600,2746379593275133584459064976784,6596095888094645606758451183394760
%N A186245 a(n) = binomial(n^2, 2*n).
%H A186245 Michael De Vlieger, <a href="/A186245/b186245.txt">Table of n, a(n) for n = 2..205</a>
%t A186245 Array[Binomial[#^2, 2 #] &, 13, 2] (* _Michael De Vlieger_, May 21 2021 *)
%o A186245 (Python)
%o A186245 import math
%o A186245 for n in range(2,22):
%o A186245     x = n*n
%o A186245     y = n+n
%o A186245     print(math.factorial(x) / (math.factorial(x-y) * math.factorial(y)), end=',')
%Y A186245 Cf. A014062.
%K A186245 nonn
%O A186245 2,2
%A A186245 _Alex Ratushnyak_, Aug 18 2012