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A138970 Positions of the primes congruent to 1 mod 4 when all primes except 2 are listed in order. 2

%I

%S 2,5,6,9,11,12,15,17,20,23,24,25,28,29,32,34,36,39,41,43,44,49,50,52,

%T 54,56,58,59,61,64,65,67,69,70,73,76,77,78,79,81,83,86,87,88,96,97,99,

%U 101,103,105,107,109,111,112,115,118,120,121,122,125,126,129,133,134,135

%N Positions of the primes congruent to 1 mod 4 when all primes except 2 are listed in order.

%C Complement of A138971 (positions of primes congruent to 3 mod 4).

%H Harvey P. Dale, <a href="/A138970/b138970.txt">Table of n, a(n) for n = 1..1000</a>

%t Position[Table[If[Mod[p,4]==1,1,0],{p,Prime[Range[2,200]]}],1]//Flatten (* _Harvey P. Dale_, Jun 22 2021 *)

%Y Cf. A138971.

%K nonn

%O 1,1

%A _Clark Kimberling_, Apr 05 2008

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Last modified November 30 22:59 EST 2021. Contains 349426 sequences. (Running on oeis4.)