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%I #11 Sep 04 2022 23:03:42
%S 3,7,31,127,12207031,8191,131071,524287,11111111111111111111111,
%T 7369130657357778596659,2147483647,
%U 19013087418896543607659206142267856546797091624826498592389251997,7538867501749984216983927242653776257689563451,26656068987980386414408582952871386493955339704241
%N Let p be the n-th prime; Cp(x) be the p-th cyclotomic polynomial (x^p-1)/(x-1); a(n) is the first prime Cp(x) after Cp(1).
%F a(n) = A085399(prime(n)).
%e a(5)=12207031 because 11 is the 5th prime; C11(x) is composite for x=2,3,4 and C11(5)=12207031 is prime.
%Y Cf. A066180, A085399.
%K nonn
%O 1,1
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 14 2003
%E Edited by _Don Reble_, Jun 28 2003