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Greatest prime factor of prime(n)^n+1.
3

%I #21 Jul 08 2023 14:08:04

%S 3,5,7,1201,13421,28393,22796593,563377,1117,470925821,1048563011,

%T 3512477579761,644522798011,22021301,24317675453761,

%U 14189041365214758401,21199857783625129028395239857,13842121,292354984050175817,613624820402521

%N Greatest prime factor of prime(n)^n+1.

%H Hugo Pfoertner and Amiram Eldar, <a href="/A069463/b069463.txt">Table of n, a(n) for n = 1..82</a> (terms 1..50 from Hugo Pfoertner)

%H Dario Alpern, <a href="https://www.alpertron.com.ar/ECM.HTM">Factorization using the Elliptic Curve Method.</a>

%H FactorDB, <a href="http://factordb.com/index.php?query=431%5E83%2B1">Status of 431^83+1</a>.

%F a(n) = A006530(A062006(n)).

%e A000040(10)^10+1 = 29^10+1 = 420707233300202 = 2*421*1061*470925821, therefore a(10) = 470925821.

%t Table[FactorInteger[Prime[n]^n+1][[-1,1]],{n,20}] (* _Harvey P. Dale_, Aug 23 2019 *)

%Y Cf. A069460.

%Y Cf. A006530, A062006.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Mar 24 2002

%E More terms from _Hugo Pfoertner_, May 21 2004