cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A184388 a(n) = product of numbers from 1 to sigma(n), where sigma(n) = A000203(n).

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%I A184388 #8 Apr 09 2019 15:44:43
%S A184388 1,6,24,5040,720,479001600,40320,1307674368000,6227020800,
%T A184388 6402373705728000,479001600,304888344611713860501504000000,
%U A184388 87178291200,620448401733239439360000,620448401733239439360000,8222838654177922817725562880000000,6402373705728000
%N A184388 a(n) = product of numbers from 1 to sigma(n), where sigma(n) = A000203(n).
%F A184388 a(n) = sigma(n)! = Product_(i = 1,…,sigma(n)) i = A000142(A000203(n)) = (A000203(n))!.
%e A184388 For n = 4; sigma(4) = 7; a(n) = 1*2*3*4*5*6*7 = 5040.
%t A184388 DivisorSigma[1,Range[20]]! (* _Harvey P. Dale_, Apr 09 2019 *)
%o A184388 (PARI) a(n)=sigma(n)! \\ _Charles R Greathouse IV_, Feb 13 2013
%Y A184388 Cf. A184387, A184389, A184390, A184391, A130674.
%K A184388 nonn
%O A184388 1,2
%A A184388 _Jaroslav Krizek_, Jan 12 2011
%E A184388 Corrected and extended by _Harvey P. Dale_, Apr 09 2019