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%I A184391 #15 Jun 25 2022 21:54:19
%S A184391 1,2,6,40320,120,371993326789901217467999448150835200000000,5040,
%T A184391 126886932185884164103433389335161480802865516174545192198801894375214704230400000000000000,
%U A184391 10888869450418352160768000000
%N A184391 a(n) = product of numbers from 1 to A007955(n).
%H A184391 Robert P. P. McKone, <a href="/A184391/b184391.txt">Table of n, a(n) for n = 1..11</a>
%F A184391 a(n) = A007955(n)! = A000142(A007955(n)).
%t A184391 A184391[n_] := Product[i, {i, 1, n^(DivisorSigma[0, n]/2)}]; Table[A184391[n], {n, 1, 9}] (* _Robert P. P. McKone_, Feb 04 2021 *)
%o A184391 (Python)
%o A184391 from math import isqrt, factorial
%o A184391 from sympy import divisor_count
%o A184391 def A184391(n): return factorial((isqrt(n) if (c:=divisor_count(n)) & 1 else 1)*n**(c//2)) # _Chai Wah Wu_, Jun 25 2022
%Y A184391 Cf. A184387, A184388, A184389, A184390, A130674.
%K A184391 nonn
%O A184391 1,2
%A A184391 _Jaroslav Krizek_, Jan 12 2011
%E A184391 a(9) from _Robert P. P. McKone_, Feb 04 2021

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