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%I #13 Jul 28 2016 21:49:38
%S 1,1,3,2,16,2,64,3,4,8,1024,5,4096,32,48,24,65536,10,262144,12,192,
%T 512,4194304,15,400,2048,900,48,268435456,24,1073741824,60,3072,32768,
%U 5184,35,68719476736,131072,12288,42,1099511627776,96,4398046511104
%N Least k such that n divides d(k*n) (d = A000005).
%e a(5) = 16 because 5 divides A000005(16*5) = 10.
%e a(40) = 42 because 40 divides A000005(42*40) = 40.
%o (PARI) a(n) = if(isprime(n) && n>3, 2^(n-1), {my(k=1); while(numdiv(k*n) % n != 0, k++); k; })
%Y Cf. A000005, A076931.
%K nonn
%O 1,3
%A _Altug Alkan_, Jul 28 2016
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