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 A128970 a(n) is the n-th prime of the form n*x^2+1. 0

%I

%S 2,19,193,101,35281,727,2269,18433,15877,7841,247501,10093,35153,

%T 727777,47041,33857,2913733,19603,1076237,486721,806737,55001,1907713,

%U 345601,193601,7581601,1037233,84701,42599377,337081,3797501,2654209

%N a(n) is the n-th prime of the form n*x^2+1.

%e a(6) is 727 because 6*1^2+1=7, 6*4^2+1=97, 6*5^2+1=151, 6*9^2+1=487, 6*10^2+1=601 and 6*11^2+1=727 are the first 6 primes of the form 6x^2+1.

%K nonn

%O 1,1

%A _John L. Drost_, Apr 28 2007

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Last modified October 26 18:09 EDT 2020. Contains 338027 sequences. (Running on oeis4.)