Mathematical constant

A mathematical constant is a quantity used in mathematics that does not change its value. A constant is thus the opposite of a variable.

π ≈ 3.14159 26535 89793 23846 26433 83279 502 (Pi, Archimedes' constant or Ludoph's number, after Ludolph van Ceulen [general (transcendental)])

e ≈ 2.71828 18284 59045 (Napier's constant, base of Natural logarithm [general (transcendental)])

γ ≈ 0.57721 56649 01532 (Euler-Mascheroni's constant, [general, number theory (?)])

φ ≈ 1.61803 39887 49894 (Golden ratio [general (algebraic)])

δ ≈ 4.66920 16091 (Feigenbaum constant [bifurcation])

α ≈ 2.50290 78750 (Feigenbaum constant [bifurcation])

C₂ ≈ 0.66016 11815 84686 95739 27812 11001 45 (Twin prime constant [number theory])

M₁ ≈ 0.26149 72128 (Mertens constant [number theory])

B₂ ≈ 1.90216 05823 (Brun's constant for twin prime [number theory])

B₄ ≈ 0.87058 83800 (Brun's constant for prime quadruplets [number theory])

Λ > – 2.7 · 10^-9 (de Bruijn-Newman constant [number theory])

K ≈ 0.91596 55941 77 (Catalan's constant [combinatorics])

B´_L ≈ 1.0836 6 (Legendre's constant [number theory])

μ ≈ 1.45136 92348 (Ramanujan-Soldner constant, Soldner constant [number theory])

E_B ≈ 1.60669 51524 15291 763 (Erdös-Borwein constant [number theory] (irrational)

External links:

Inverse symbolic calculator (tells you how a given number can be constructed from mathematical constants): http://www.cecm.sfu.ca/projects/ISC/