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A284440 Smallest number k such that A049559(k) / A187730(k) = n. 2

%I #16 Oct 15 2019 08:41:16

%S 1,21,91,65,451,217,2059,1665,4699,2101,24564,1729,74023,9017,13051,

%T 4097,60691,5833,278693,20801,142003,10649,47611,54145,116251,47321,

%U 19684,21953,338083,54901,501643,53505,141571,219641,169051,80353,386059,515509,453259,16401

%N Smallest number k such that A049559(k) / A187730(k) = n.

%C For every n, a(n)-1 is not squarefree.

%H Amiram Eldar, <a href="/A284440/b284440.txt">Table of n, a(n) for n = 1..450</a>

%t a[n_]:= Block[{k=1}, While[GCD[k - 1, EulerPhi[k]]/GCD[CarmichaelLambda[k], k - 1] != n, k++]; k]; Table[a[n], {n, 40}] (* _Indranil Ghosh_, Mar 27 2017 *)

%o (PARI) a(n)={my(k=1); while(gcd(k - 1, eulerphi(k))/gcd(lcm(znstar(k)[2]),k - 1) != n, k++); k}; \\ _Indranil Ghosh_, Mar 27 2017

%Y Cf. A284089.

%K nonn

%O 1,2

%A _Thomas Ordowski_ and _Altug Alkan_, Mar 27 2017

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)