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%I M1343 #44 Oct 10 2023 06:21:33
%S 2,5,7,257,521,97,911,673,530713,27961,58367,2227777,79301,176597,
%T 142111,67280421310721,45957792327018709121,33388093,870542161121,
%U 4406613081041681,22864311556633,73194743542229,1522029233,27250359649
%N a(n) = largest prime factor of n^n + 1.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Tyler Busby, <a href="/A007571/b007571.txt">Table of n, a(n) for n = 1..148</a> (terms 1..123 from Hugo Pfoertner, terms 124..135 from Yurii Ivanov)
%H factordb, <a href="http://factordb.com/index.php?query=n%5En%2B1&use=n&perpage=20&format=1&sent=1&PR=1&PRP=1&C=1&CF=1&U=1&FF=1&VP=1&EV=1&OD=1&VC=1&n=148">Status of 148^148+1 ... 167^167+1</a>.
%F a(n) = A006530(A014566(n)). - _Michel Marcus_, Aug 24 2019
%t Table[ FactorInteger[ n^n + 1, FactorComplete -> True ] [ [ -1, 1 ] ], {n, 1, 25} ]
%o (PARI) for(k=1, 24, my(x=factor(k^k+1), f=x[#x[, 1], 1]); print1(f,", ")) \\ _Hugo Pfoertner_, Aug 23 2019
%o (Magma) [Max(PrimeDivisors(n^n+1)):n in [1..24]]; // _Marius A. Burtea_, Aug 24 2019
%Y Cf. A006530, A006486, A014566, A056790.
%K nonn,hard
%O 1,1
%A _N. J. A. Sloane_, _Robert G. Wilson v_
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