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%I #16 Sep 17 2019 09:56:15
%S 1,2,6,3,6,6,15,4,10,6,12,7,28,15,6,5,18,10,20,7,15,12,24,8,21,28,10,
%T 15,60,6,63,8,12,18,28,11,76,20,28,9,81,15,46,12,10,24,48,8,27,21,18,
%U 28,110,10,24,15,20,60,120,7,243,63,15,15,28,12,68,18,24,28
%N Least k such that n divides d(k!) where d = A000005 (k > 0).
%H Harvey P. Dale, <a href="/A275476/b275476.txt">Table of n, a(n) for n = 1..1000</a>
%e a(3) = 6 because A000005(6!) = 30 is divisible by 3.
%t Table[k = 1; While[! Divisible[DivisorSigma[0, k!], n], k++]; k, {n, 120}] (* _Michael De Vlieger_, Aug 07 2016 *)
%t With[{c=Table[{k,DivisorSigma[0,k!]},{k,250}]},Table[SelectFirst[ c, Divisible[ #[[2]],n]&],{n,70}]][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Sep 17 2019 *)
%o (PARI) a(n) = {my(k = 1); while(numdiv(k!) % n != 0, k++); k; }
%Y Cf. A000005, A027423.
%K nonn
%O 1,2
%A _Altug Alkan_, Jul 29 2016
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