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.
%I A229334 #7 Dec 11 2015 22:04:33 %S A229334 1,2,2,24,2,20736,2,20736,24,20736,2,11501279977342425366528000000,2, %T A229334 20736,20736,309586821120,2,11501279977342425366528000000,2, %U A229334 11501279977342425366528000000,20736,20736,2 %N A229334 Product of numbers of elements of nonempty subsets of divisors of n. %C A229334 Number of nonempty subsets of divisors of n = A100587(n). %C A229334 Also product of sizes of all the subsets of set of divisors of n. %F A229334 a(n) = product[k=1..tau(n)] k^C(tau(n),k) = product[k=1..tau(n)] k^(tau(n)!/((tau(n)-k)!*k!)). %e A229334 For n = 4; divisors of 4: {1, 2, 4}; nonempty subsets of divisors of n: {1}, {2}, {4}, {1, 2}, {1, 4}, {2, 4}, {1, 2, 4}; product of numbers of elements of subsets = 1*1*1*2*2*2*3 = 24. %e A229334 For n = 4; tau(4) = 3; a(4) = [1^(3!/((3-1)!*1!))] * [2^(3!/((3-2)!*2!))] * [3^(3!/((3-3)!*3!))] = 1^3 * 2^3 * 3^1 = 24. %t A229334 Table[Times @@ Rest[Length /@ Subsets[Divisors[n]]], {n, 23}] (* _T. D. Noe_, Oct 01 2013 *) %Y A229334 Cf. A000005, A100587, A229333. %K A229334 nonn %O A229334 1,2 %A A229334 _Jaroslav Krizek_, Sep 30 2013