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A111745 a(2k-1) = k-th prime congruent to 3 mod 4, a(2k) = k-th prime congruent to 1 mod 4. 4
3, 5, 7, 13, 11, 17, 19, 29, 23, 37, 31, 41, 43, 53, 47, 61, 59, 73, 67, 89, 71, 97, 79, 101, 83, 109, 103, 113, 107, 137, 127, 149, 131, 157, 139, 173, 151, 181, 163, 193, 167, 197, 179, 229, 191, 233, 199, 241, 211, 257, 223, 269, 227, 277, 239, 281, 251, 293, 263 (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..1000

FORMULA

a(n)=A108546(n+1). [From R. J. Mathar, Aug 15 2008]

MATHEMATICA

Module[{prs=Prime[Range[70]], m3, m1, min}, m3=Select[prs, Mod[#, 4]==3&]; m1=Select[prs, Mod[#, 4]==1&]; min=Min[Length[m1], Length[m3]]; Riffle[ Take[m3, min], Take[m1, min]]] (* Harvey P. Dale, Apr 15 2012 *)

CROSSREFS

Cf. bisections A002144, A002145.

Sequence in context: A071810 A137576 A161329 * A098957 A143245 A018205

Adjacent sequences:  A111742 A111743 A111744 * A111746 A111747 A111748

KEYWORD

nonn

AUTHOR

Jon Perry, Nov 19 2005

EXTENSIONS

Edited, corrected and extended by Franklin T. Adams-Watters, Jul 19 2006

Corrected by T. D. Noe, Nov 15 2006

STATUS

approved

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Last modified December 8 08:56 EST 2021. Contains 349594 sequences. (Running on oeis4.)