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a(0) = 1, a(1) = 2; thereafter a(n) = prime(mod(a(n-1),100))+1.
0

%I #12 Feb 24 2023 12:05:52

%S 1,2,4,8,20,72,360,282,422,80,410,30,114,44,194,492,480,410,30,114,44,

%T 194,492,480,410,30,114,44,194,492,480,410,30,114,44,194,492,480,410,

%U 30,114,44,194,492,480,410,30,114,44,194,492,480,410,30,114,44,194,492,480

%N a(0) = 1, a(1) = 2; thereafter a(n) = prime(mod(a(n-1),100))+1.

%C Starting with the tenth term, cycles every seven terms. - _Robert G. Wilson v_, Dec 13 2005

%D Zak Seidov, Posting to Seq Fan mailing list, Nov 28 2005

%e a(2) = prime(2) + 1 = 3+1 = 4, a(3) = prime(4) + 1 = 19+1 = 20, and so on. But remember to reduce the primes mod 100 when they get large. - _N. J. A. Sloane_, Feb 24 2023

%t Join[{1},NestList[Prime[Mod[#,100]]+1&,2,100]] (* _Harvey P. Dale_, Feb 24 2023 *)

%K nonn

%O 0,2

%A _N. J. A. Sloane_, Nov 24 2005

%E More terms from _Robert G. Wilson v_, Dec 13 2005

%E Revised by _N. J. A. Sloane_, Feb 24 2023