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%I #7 Jan 04 2024 14:51:34
%S 11,13,157,29,22621,157,4943,233,80749,22621,266981089,20593,20369233,
%T 13063,22621,260753,74876782031,80749,29043636306420266077,85403261,
%U 8177824843189,57154490053,321218438243,2227777,12629757106815551,20369233,86769286104133
%N Largest prime factor of 12^n - 1.
%H Max Alekseyev, <a href="/A366718/b366718.txt">Table of n, a(n) for n = 1..310</a>
%H J. Brillhart et al., <a href="http://dx.doi.org/10.1090/conm/022">Factorizations of b^n +- 1</a>, Contemporary Mathematics, Vol. 22, Amer. Math. Soc., Providence, RI, 3rd edition, 2002.
%F a(n) = A006530(A024140(n)).
%t Table[FactorInteger[12^n - 1][[-1, 1]], {n, 40}]
%o (Magma) [Maximum(PrimeDivisors(12^n-1)): n in [1..40]];
%Y Cf. A024140, A006530, A005420, A074477, A274906, A074479, A274907, A074249, A274908, A274909, A005422, A274910, A366707, A366708, A366709, A366710, A366711, A366717, A366720.
%K nonn
%O 1,1
%A _Sean A. Irvine_, Oct 17 2023