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%I #28 May 28 2023 15:40:45
%S 2,94,334,4422,23969,303493,303493,606529,28725046,92865581,397316305,
%T 511883558,848516256,23738949809,144899085865,469694200388,
%U 3800553021301,8571139291304,63858322306341,90990757864814
%N a(n) is the least integer k such that the k-th, (k+1)-th, ..., (k+n-1)-th primes are congruent to 3 mod 8.
%C a(n) is also the minimal rank where n consecutive 2's appear in A023512.
%C The sequence is infinite by Shiu's theorem.
%F a(n) = primepi(A057632(n)). - _Amiram Eldar_, May 13 2023
%e For n=2, a(2) = 94 because prime(94)+1 = 492 = 4*123, prime(95)+1 = 500 = 4*125 are the first two consecutive primes p such that p+1 is divisible by 4 and not by 8.
%Y Cf. A057632, A023512.
%Y Cf. A363016 (with 1 mod 4).
%K nonn,more
%O 1,1
%A _Léo Gratien_, May 13 2023
%E a(19)-a(20) from _Martin Ehrenstein_, May 28 2023
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