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A215460 a(n) = floor(n!^2 / n^n).

%I A215460 #21 Aug 05 2025 21:35:59
%S A215460 1,1,1,2,4,11,30,96,339,1316,5584,25733,128025,683949,3905083,
%T A215460 23731187,152934464,1041782238,7479469995,56448098958,446768591341,
%U A215460 3700276748921,32007269639380,288630046441757,2708888570942365,26419890078249485,267389254029561667,2804508541393392135,30446382653772707171,341729529206733994569
%N A215460 a(n) = floor(n!^2 / n^n).
%H A215460 Paolo Xausa, <a href="/A215460/b215460.txt">Table of n, a(n) for n = 1..500</a>
%e A215460 a(4) = floor((4!)^2 / (4^4)) = floor(24^2 / 256) = floor(2.25) = 2.
%t A215460 A215460[n_] := Quotient[n!^2, n^n];
%t A215460 Array[A215460, 30] (* _Paolo Xausa_, Aug 05 2025 *)
%o A215460 (Python)
%o A215460 f = 1
%o A215460 for n in range(1,33):
%o A215460     print(f*f // n**n)
%o A215460     f *= n+1
%Y A215460 Cf. A064546, A063709, A055775.
%K A215460 nonn
%O A215460 1,4
%A A215460 _Alex Ratushnyak_, Aug 11 2012
%E A215460 More terms from _Paolo Xausa_, Aug 05 2025