Linnik's constant 
is the constant appearing in Linnik's theorem.
Heath-Brown (1992) has shown that 
, and Schinzel, Sierpiński, and Kanold (Ribenboim
1989) have conjectured that 
.
Linnik's Constant
See also
Linnik's TheoremExplore with Wolfram|Alpha
References
Finch, S. R. "Linnik's Constant." §2.12 in Mathematical Constants. Cambridge, England: Cambridge University Press, pp. 127-130, 2003.Guy, R. K. Unsolved Problems in Number Theory, 2nd ed. New York: Springer-Verlag, p. 13, 1994.Heath-Brown, D. R. "Zero-Free Regions for Dirichlet
-Functions and the Least Prime in an
Arithmetic Progression." Proc. London Math. Soc. 64, 265-338,
1992.Ribenboim, P. The
New Book of Prime Number Records. New York: Springer-Verlag, 1989.Referenced on Wolfram|Alpha
Linnik's ConstantCite this as:
Weisstein, Eric W. "Linnik's Constant." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/LinniksConstant.html