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%I #19 Oct 29 2024 03:28:06
%S 1,3,5,41,103,1237,433,2389,2711,145007,523,164611949,232603841,
%T 201069629,132267077,35951249665217,204405098431,392881768421,
%U 52255141388393,8098687,43894318766250120011,386270005143001056097
%N a(1) = 1, a(n) = largest prime divisor of b(n), where b(1) = 1, b(n) = n*b(n-1) + 1 = A002627(n).
%H Amiram Eldar, <a href="/A096058/b096058.txt">Table of n, a(n) for n = 1..69</a>
%F a(n) = A006530(A002627(n)).
%e a(4) = 41 because b(3) = 3*b(2)+1 = 3*3+1 = 10 and 4*10+1 = 41, which is prime.
%e b(n) = 1, 3, 10, 41, ... with largest prime divisors a(n) = 1, 3, 5, 41, ...
%t nxt[{n_,a_}]:={n+1,a(n+1)+1}; FactorInteger[#][[-1,1]]&/@NestList[nxt,{1,1},25][[;;,2]] (* _Harvey P. Dale_, Jul 22 2024 *)
%Y Cf. A096057, A006530, A002627, A096057.
%K nonn
%O 1,2
%A _Amarnath Murthy_, Jun 17 2004
%E Corrected and extended by _Ray G. Opao_, Aug 02 2004
%E Edited by _Jonathan Sondow_, Jan 09 2005