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A392296
Primes p such that Pi_{5,2}(p) + Pi_{5,3}(p) - Pi_{5,1}(p) - Pi_{5,4}(p) = 0, where Pi_{m,n}(p) denotes the number of primes q <= p with q == n (mod m).
6
2082927199, 2082927467, 2082928123, 2082928189, 2082928201, 2082940213, 2082940667, 2082940787, 2082940813, 2082940837, 2082940967, 2082941033, 2082941093, 2082941143, 2082941221, 2082941309, 2082941521, 2082941579, 2082943987, 2082944183, 2082944317, 2082944323, 2082944477, 2082944531
OFFSET
1,1
COMMENTS
In general, assuming the strong form of the Riemann Hypothesis, if 0 < a, b < k are integers, gcd(a, k) = gcd(b, k) = 1, a is a quadratic residue and b is a quadratic nonresidue mod k, then Pi(k,b)(n) > Pi(k,a)(n) occurs more often than not. Pi(a,b)(x) denotes the number of primes in the arithmetic progression a*k + b less than or equal to x. This phenomenon is called "Chebyshev's bias". (See Wikipedia link and especially the links in A007350.)
LINKS
Jianing Song, Table of n, a(n) for n = 1..1081 (all terms up to the first region where Pi_{5,2}+Pi_{5,3}-Pi_{5,1}-Pi_{5,4} is negative)
Andrew Granville and Greg Martin, Prime number races, Amer. Math. Monthly, 113 (No. 1, 2006), 1-33.
Wikipedia, Chebyshev's bias
PROG
(PARI) my(i=0); forprime(p=2, 2083000000, i+=kronecker(5, p); if(i==0, print1(p, ", ")))
CROSSREFS
Cf. prime indices of -1, 0, 1, 2, 3 in A321857: A392295, this sequence, A392297, A392298, A392299.
Sequence in context: A180618 A292546 A287593 * A392295 A216012 A096561
KEYWORD
nonn
AUTHOR
Jianing Song, Jan 08 2026
STATUS
approved