

A096448


Primes p such that the number of primes less than p equal to 1 mod 4 is one less than the number of primes less than p equal to 3 mod 4.


13



5, 11, 17, 23, 31, 41, 47, 59, 67, 103, 127, 419, 431, 439, 461, 467, 1259, 1279, 1303, 26833, 26849, 26881, 26893, 26921, 26947, 615883, 616769, 616787, 616793, 616829, 617051, 617059, 617087, 617257, 617473, 617509, 617647, 617681, 617731, 617819
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OFFSET

1,1


COMMENTS

First term prime(2) = 3 is placed on 0th row.
If prime(n1) = +1 mod 4 is on kth row then we put prime(n) on (k1)st row.
If prime(n1) = 1 mod 4 is on kth row then we put prime(n) on (k+1)st row.
This process makes an array of prime numbers:
3, 7, 19, 43, ....0th row
5, 11, 17, 23, 31, 41, 47, 59, 67, 103, 127, ....first row
13, 29, 37, 53, 61, 71, 79, 101, 107, 113 ....2nd row
73, 83, 97, 109, ....3rd row
89, ....4th row


LINKS

Table of n, a(n) for n=1..40.


MATHEMATICA

Prime[#]&/@(Flatten[Position[Accumulate[If[Mod[#, 4]==1, 1, 1]&/@ Prime[ Range[ 2, 51000]]], 1]]+2) (* Harvey P. Dale, Mar 08 2015 *)


CROSSREFS

Cf. A096447A096455.
Cf. A096448A096455.
Sequence in context: A189938 A184525 A252596 * A147305 A049755 A096449
Adjacent sequences: A096445 A096446 A096447 * A096449 A096450 A096451


KEYWORD

nonn,easy


AUTHOR

Yasutoshi Kohmoto, Aug 12 2004


EXTENSIONS

More terms from Joshua Zucker, May 03 2006


STATUS

approved



