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 A111744 a(2k-1) = k-th prime of form 1 mod 4, a(2k) = k-th prime of form 3 mod 4. 1
 5, 3, 13, 7, 17, 11, 29, 19, 37, 23, 41, 31, 53, 43, 61, 47, 73, 59, 89, 67, 97, 71, 101, 79, 109, 83, 113, 103, 137, 107, 149, 127, 157, 131, 173, 139, 181, 151, 193, 163, 197, 167, 229, 179, 233, 191, 241, 199, 257, 211, 269, 223, 277, 227, 281, 239, 293, 251, 313 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The graph shows the "race" between the two types of primes. - T. D. Noe, Nov 15 2006 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..10000 MATHEMATICA Module[{nn=100, pr, m1, m3, len}, pr=Prime[Range[nn]]; m1=Select[pr, Mod[#, 4] == 1&]; m3=Select[pr, Mod[#, 4]==3&]; len=Min[Length[m1], Length[m3]]; Flatten[ Thread[ {Take[m1, len], Take[m3, len]}]]] (* Harvey P. Dale, Jun 29 2019 *) CROSSREFS Sequence in context: A300940 A131939 A205522 * A083781 A349156 A206435 Adjacent sequences:  A111741 A111742 A111743 * A111745 A111746 A111747 KEYWORD nonn AUTHOR Jon Perry, Nov 19 2005 EXTENSIONS Corrected and extended by Wendy Kalasky (wkk107(AT)psu.edu), Apr 25 2006 Corrected by T. D. Noe, Nov 15 2006 STATUS approved

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Last modified December 6 16:37 EST 2021. Contains 349567 sequences. (Running on oeis4.)