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A096451
Primes p such that the number of primes less than p equal to 1 mod 4 is two less than the number of primes less than p equal to 3 mod 4.
3
13, 29, 37, 53, 61, 71, 79, 101, 107, 113, 131, 139, 151, 163, 199, 359, 409, 421, 433, 443, 457, 479, 1223, 1231, 1249, 1277, 1283, 1291, 1301, 1307, 1399, 1423, 1439, 8699, 8779, 26821, 26951, 26959, 26987, 27011, 27031, 615731, 615869, 615887
OFFSET
1,1
COMMENTS
First term prime(2) = 3 is placed on 0th row.
If prime(n-1) = +1 mod 4 is on k-th row then we put prime(n) on (k-1)-st row.
If prime(n-1) = -1 mod 4 is on k-th 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
Andrew Granville and Greg Martin, Prime number races, Amer. Math. Monthly, 113 (No. 1, 2006), 1-33.
MAPLE
c1:= 0; c3:= 0: p:= 2: count:= 0: Res:= NULL:
while count < 100 do
p:= nextprime(p);
if c1 = c3 - 2 then
count:= count+1;
Res:= Res, p;
fi;
if p mod 4 = 1 then c1:=c1+1
else c3:= c3+1
fi
od:
Res; # Robert Israel, Nov 07 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Yasutoshi Kohmoto, Aug 12 2004
EXTENSIONS
More terms from Joshua Zucker, May 03 2006
STATUS
approved