|
%I #9 Aug 12 2016 13:58:18
%S 1,3,2,3,4,3,10,5,5,4,9,3,6,10,4,7,8,5,14,4,11,9,12,5,21,6,14,10,42,4,
%T 6,11,9,8,14,5,36,14,6,5,22,11,35,9,5,12,24,7,13,21,8,7,69,14,9,10,14,
%U 42,60,4,21,6,14,12,8,9,45,8,12,14,20,5,10,36,21,14,10,6,40,8,14,22,81,11
%N Least k such that n divides sigma(k!) (k > 0).
%H Chai Wah Wu, <a href="/A275769/b275769.txt">Table of n, a(n) for n = 1..10000</a>
%e a(5) = 4 because sigma(4!) = 60 is divisible by 5.
%t Table[k = 1; While[! Divisible[DivisorSigma[1, k!], n], k++]; k, {n, 84}] (* _Michael De Vlieger_, Aug 08 2016 *)
%o (PARI) a(n) = {my(k=1); while(sigma(k!) % n != 0, k++); k; }
%Y Cf. A000203, A062569.
%K nonn
%O 1,2
%A _Altug Alkan_, Aug 08 2016
|
