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%I #13 Oct 23 2023 07:19:26
%S 5,13,47,673,1093,4789,15887,6961,7079,1853387,5636791,16319158451,
%T 46975091221,97536826417,9513432505744326182381,
%U 2335222008886384800739,7440517660385876970522347503153,83914607657246408236765553419,1960358081272210906656999086971746456168551
%N a(0) = 5; for n > 0, a(n) is the greatest prime factor of PP(a(n-1))*a(n-1)-2 where PP(n) is an abbreviation for PreviousPrime(n).
%C Some of the larger entries may only correspond to probable primes.
%H Tyler Busby, <a href="/A082132/b082132.txt">Table of n, a(n) for n = 0..22</a>
%o (PARI) p=5;for(k=1,20,print1(p,",");p=precprime(p-1)*p-2;f=factor(p);s=matsize(f)[1];p=f[s,1]) \\ _Rick L. Shepherd_, Dec 19 2004
%Y Cf. A082021, A031441, A031442.
%K nonn
%O 0,1
%A _Yasutoshi Kohmoto_, May 10 2003
%E Edited by _Rick L. Shepherd_, Dec 19 2004
%E a(18) from _Tyler Busby_, Oct 22 2023
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