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Least positive k such that d(n) divides d(n+k) (d = A000005).
2

%I #13 Mar 02 2023 16:52:55

%S 1,1,2,5,1,2,1,2,3,4,1,6,1,1,6,32,1,2,1,8,1,2,1,6,3,1,3,4,1,10,1,12,1,

%T 1,3,64,1,1,1,2,1,12,1,1,5,5,1,32,1,2,3,8,1,2,1,10,1,2,1,12,1,3,5,128,

%U 1,4,1,4,1,8,1,12,1,3,1,8,1,10,1,32,31,2,1,6,1,1,1,14,1,6,2,4,1,1,1,12,1,1,9,80

%N Least positive k such that d(n) divides d(n+k) (d = A000005).

%C a(A057922(n)) = 1. - _Michel Marcus_, Aug 01 2016

%H Antti Karttunen, <a href="/A275479/b275479.txt">Table of n, a(n) for n = 1..20000</a>

%e a(10) = 4 because A000005(10) divides A000005(10+4).

%o (PARI) a(n) = {my(k = 1); while(numdiv(n+k) % numdiv(n) != 0, k++); k; }

%Y Cf. A000005, A057922, A171937, A275478.

%K nonn

%O 1,3

%A _Altug Alkan_, Jul 29 2016

%E Data section extended up to a(100) by _Antti Karttunen_, Mar 02 2023