cp's OEIS Frontend

A077198 a(n) = lambda(sigma(n)), where lambda(n) is the Carmichael lambda function, which gives the smallest integer m such that k^m = 1 mod n for all integers k relatively prime to n.

%I A077198 #8 Nov 18 2017 08:46:10
%S A077198 1,2,2,6,2,2,2,4,12,6,2,6,6,2,2,30,6,12,4,6,8,6,2,4,30,6,4,6,4,6,8,6,
%T A077198 4,18,4,12,18,4,6,12,6,8,10,6,12,6,4,30,18,30,6,42,18,4,6,4,4,12,4,6,
%U A077198 30,8,12,126,6,12,16,6,8,12,6,12,36,18,30,12,8,6,4,30,110,6,6,24,18,10,4
%N A077198 a(n) = lambda(sigma(n)), where lambda(n) is the Carmichael lambda function, which gives the smallest integer m such that k^m = 1 mod n for all integers k relatively prime to n.
%H A077198 Antti Karttunen, <a href="/A077198/b077198.txt">Table of n, a(n) for n = 1..16384</a>
%H A077198 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A077198 a(n) = A002322(A000203(n)). - _Antti Karttunen_, Nov 18 2017
%t A077198 Table[CarmichaelLambda[DivisorSigma[1, n]], {n, 1, 100}]
%o A077198 (PARI) A077198(n) = lcm(znstar(sigma(n))[2]); \\ _Antti Karttunen_, Nov 18 2017
%Y A077198 Cf. A000203, A002322.
%Y A077198 Cf. also A062401, A290088.
%K A077198 nonn
%O A077198 1,2
%A A077198 _Joseph L. Pe_, Nov 30 2002