Pi π 3.141592653589793 3.14159 26535 89793 23846 -1900 1900 to 1600 BCE false false true true Tau τ 6.283185307179586 6.28318 53071 79586 47692 -1900 1900 to 1600 BCE false false true true Square root of 2, Pythagoras constant √2 1.4142135623730951 1.41421 35623 73095 04880 -1800 1800 to 1600 BCE false true true true Square root of 3, Theodorus' constant √3 1.7320508075688772 1.73205 08075 68877 29352 -465 465 to 398 BCE false true true true Zero 0 0 0 -300 300 to 100 BCE true true true true Phi, Golden ratio φ or ϕ 1.618033988749895 1.61803 39887 49894 84820 -300 ~300 BCE false true true true Silver ratio σ 2.414213562373095 2.41421 35623 73095 04880 -300 ~300 BCE false true true true Negative one −1 -1 −1 -300 300 to 200 BCE true true true true Cube root of 2, Delian constant ³√2 1.2599210498948732 1.25992 10498 94873 16476 46 46 to 120 CE false true true true Imaginary unit i 0 + 1i 1501 1501 to 1576 false true true true Connective constant for the hexagonal lattice μ 1.8477590650225735 1.84775 90650 22573 51225 1593 1593 false true true true Kepler–Bouwkamp constant K^′ 0.1149420448532962 0.11494 20448 53296 20070 1596 1596 Wallis's constant 2.0945514815423265 2.09455 14815 42326 59148 1616 1616 to 1703 false true true true Euler's number e 2.718281828459045 2.71828 18284 59045 23536 1618 1618 false false true Natural logarithm of 2 ln2 0.6931471805599453 0.69314 71805 59945 30941 1619 1619 & 1668 false false true true Sophomore's dream second constant I₂ 1.2912859970626636 1.29128 59970 62663 54040 1697 1697 Lemniscate constant ϖ 2.6220575542921196 2.62205 75542 92119 81046 1718 1718 to 1798 false false true true Basel's number ζ(2) 1.6449340668482264 1.64493 40668 48226 43647 1734 1734 false false true true Euler's constant γ 0.5772156649015329 0.57721 56649 01532 86060 1735 1735 true Erdős–Borwein constant E 1.6066951524152917 1.60669 51524 15291 76378 1749 1749 false Square super-root of 2 √2ₛ 1.5596104694623694 1.55961 04694 62369 34997 1758 1758 & 1783 false false Omega constant Ω 0.5671432904097838 0.56714 32904 09783 87299 1758 1758 & 1783 false false Apéry's constant ζ(3) 1.2020569031595942 1.20205 69031 59594 28539 1780 1780 false true true Laplace limit 0.6627434193491816 0.66274 34193 49181 58097 1782 ~1782 false false Soldner constant μ 1.451369234883381 1.45136 92348 83381 05028 1792 1792 Gauss's constant G 0.8346268416740732 0.83462 68416 74073 18628 1799 1799 false false true Second Hermite constant γ₂ 1.1547005383792515 1.15470 05383 79251 52901 1822 1822 to 1901 false true true true First continued fraction constant C₁ 0.697774657964008 0.69777 46579 64007 98201 1855 1855 false false Ramanujan's constant 262537412640768740 262 53741 26407 68743 .99999 99999 99250 073 1859 1859 false false Glaisher–Kinkelin constant A 1.2824271291006226 1.28242 71291 00622 63687 1860 1860 Catalan's constant G 0.915965594177219 0.91596 55941 77219 01505 1864 1864 true true Dottie number D 0.7390851332151607 0.73908 51332 15160 64165 1865 1865 false false Meissel–Mertens constant M 0.26149721284764277 0.26149 72128 47642 78375 1866 1866 & 1873 Cahen's constant C 0.643410546288338 0.64341 05462 88338 02618 1891 1891 false false Gelfond's constant e^π 23.14069263277927 23.14069 26327 79269 0057 1900 1900 false false Totient summatory constant 1.3397841535743473 1.33978 41535 74347 24659 1900 1900 Second Favard constant K₂ 1.2337005501361697 1.23370 05501 36169 82735 1902 1902 to 1965 false false true true Golden angle g 2.3999632297286535 2.39996 32297 28653 32223 1907 1907 false false true true Sierpiński's constant K 2.5849817595792532 2.58498 17595 79253 21706 1907 1907 Landau–Ramanujan constant K 0.7642236535892206 0.76422 36535 89220 66299 1908 1908 First Nielsen–Ramanujan constant a₁ 0.8224670334241132 0.82246 70334 24113 21823 1909 1909 false false true true Gieseking constant V 1.0149416064096537 1.01494 16064 09653 62502 1912 1912 true true Bernstein's constant β 0.2801694990238691 0.28016 94990 23869 13303 1913 1913 Tribonacci constant ρ 1.8392867552141612 1.83928 67552 14161 13255 1914 1914 to 1963 false true true true Kempner series's value 22.92067661926415 22.92067 66192 64150 34816 1914 1914 Kempner number κ 0.8164215090218931 0.81642 15090 21893 14370 1916 1916 false false Brun's constant B₂ 1.902160583104 ≈ 1.90216 05831 04 1919 1919 Twin primes constant C₂ 0.6601618158468696 0.66016 18158 46869 57392 1922 1922 Plastic ratio ρ 1.324717957244746 1.32471 79572 44746 02596 1924 1924 false true true true Bloch's constant B 0.4332≤B≤0.4719 1925 1925 Z score for the 97.5 percentile point z_.975 1.9599639845400543 1.95996 39845 40054 23552 1925 1925 Landau's constant L 0.5<L≤0.54326 1929 1929 Landau's third constant A 0.5<A≤0.7853 1929 1929 Prouhet–Thue–Morse constant τ 0.4124540336401076 0.41245 40336 40107 59778 1929 1929 false false Golomb–Dickman constant λ 0.6243299885435508 0.62432 99885 43550 87099 1930 1930 & 1964 Constant related to the asymptotic behavior of Lebesgue constants c 0.9894312738311469 0.98943 12738 31146 95174 1930 1930 Feller–Tornier constant 𝒞_FT 0.6613170494696223 0.66131 70494 69622 33528 1932 1932 Base 10 Champernowne constant C₁₀ 0.12345678910111213 0.12345 67891 01112 13141 1933 1933 false false Salem constant σ₁₀ 1.1762808182599176 1.17628 08182 59917 50654 1933 1933 false true true true Khinchin's constant K₀ 2.6854520010653062 2.68545 20010 65306 44530 1934 1934 Lévy's constant (1) β 1.1865691104156255 1.18656 91104 15625 45282 1935 1935 Lévy's constant (2) e^β 3.2758229187218113 3.27582 29187 21811 15978 1936 1936 Linnik's constant L L ≤ 3.99 1944 1944 Copeland–Erdős constant 𝒞_CE 0.23571113171923294 0.23571 11317 19232 93137 1946 1946 false Mills' constant A 1.3063778838630806 1.30637 78838 63080 69046 1947 1947 false Third continued fraction constant C₃ 1.525135276160981 1.52513 52761 60981 20908 1948 1948 de Bruijn–Newman constant Λ 0≤Λ≤0.2 1950 1950 Porter's constant C 1.4670780794339755 1.46707 80794 33975 47289 1961 1961 Lochs constant L 0.9702701143920339 0.97027 01143 92033 92574 1964 1964 Infinite tetration of imaginary unit 0.438283 + 0.360592i 1966 1966 false DeVicci's tesseract constant 1.0074347568842794 1.00743 47568 84279 37609 1966 1966 false true true true Lieb's square ice constant 1.539600717839002 1.53960 07178 39002 03869 1967 1967 false true true true Growth rate constant of fixed polyomino (Klarner's constant) λ₂ 4.00253 < λ2 < 4.5252 1967 1967 Growth rate constant of fixed polycube λ₃ 6.3795 < λ3 < 9.3835 1967 1967 Niven's constant C 1.7052111401053678 1.70521 11401 05367 76428 1969 1969 Stephens' constant C_S 0.5759599688929454 0.57595 99688 92945 43964 1969 1969 Regular paperfolding sequence P 0.8507361882018672 0.85073 61882 01867 26036 1970 1970 false false Reciprocal Fibonacci constant ψ 3.3598856662431777 3.35988 56662 43177 55317 1974 1974 false Chvátal–Sankoff constant for the binary alphabet γ₂ 0.788071≤γ2≤0.826280 1975 1975 Feigenbaum constant δ δ 4.66920160910299 4.66920 16091 02990 67185 1975 1975 Chaitin's constants Ω In general they are uncomputables; one such number is 0.00787 49969 97812 3844. 1975 1975 false false false false Freiman's constant F 4.527829566160879 4.52782 95661 60879 14088 1975 1975 false true true true Robbins constant Δ(3) 0.6617071822671763 0.66170 71822 67176 23515 1977 1977 false false true true Fransén–Robinson constant F 2.8077702420285195 2.80777 02420 28519 36522 1978 1978 Feigenbaum constant α α 2.5029078750958926 2.50290 78750 95892 82228 1979 1979 Irrational number from Moser–de Bruijn sequence α 3.30033 3.30033 00000 00000 33003 1982 1982 false false Second du Bois-Reymond constant C₂ 0.19452804946532512 0.19452 80494 65325 11361 1983 1983 false false true Erdős–Tenenbaum–Ford constant δ 0.0860713320559342 0.08607 13320 55934 20688 1984 1984 Conway's constant λ 1.3035772690342964 1.30357 72690 34296 39125 1987 1987 false true true true Hard hexagon entropy constant κ(1) 1.3954859724793027 1.39548 59724 79302 73522 1988 1988 false true true true Hafner–Sarnak–McCurley constant σ 0.353236371854996 0.35323 63718 54995 98454 1991 1991 Backhouse's constant B 1.4560749485826896 1.45607 49485 82689 67139 1995 1995 Viswanath constant V 1.1319882487943 1.13198 82487 943 1997 1997 Komornik–Loreti constant q 1.787231650182966 1.78723 16501 82965 93301 1998 1998 false false Embree–Trefethen constant β^⋆ 0.70258 0.70258 1999 1999 Heath-Brown–Moroz constant C 0.001317641154853178 0.00131 76411 54853 17810 1999 1999 MRB constant S 0.18785964246206713 0.18785 96424 62067 12024 1999 1999 Prime constant ρ 0.41468250985111166 0.41468 25098 51111 66024 1999 1999 false Somos' quadratic recurrence constant σ 1.6616879496335941 1.66168 79496 33594 12129 1999 1999 Foias constant α 1.1874523511265012 1.18745 23511 26501 05459 2000 2000 One 1 1 1 Prehistory true true true true Two 2 2 2 Prehistory true true true true One half 1/2 0.5 0.5 Prehistory true true true true Square root of 5 √5 2.23606797749979 2.23606 79774 99789 69640 false true true true Cube root of 3 ³√3 1.4422495703074083 1.44224 95703 07408 38232 false true true true Twelfth root of 2 ¹²√2 1.0594630943592953 1.05946 30943 59295 26456 false true true true Supergolden ratio ψ 1.465571231876768 1.46557 12318 76768 02665 false true true true Liouville's constant L 0.110001 0.11000 10000 00000 00000 0001 Before 1844 false false Universal parabolic constant P 2.295587149392638 2.29558 71493 92638 07403 Before 1891 false false true true Gelfond–Schneider constant 2^(√2) 2.665144142690225 2.66514 41426 90225 18865 Before 1902 false false Gompertz constant δ 0.5963473623231941 0.59634 73623 23194 07434 Before 1948 true Van der Pauw constant π/ln2 4.532360141827194 4.53236 01418 27193 80962 Before 1958 false Magic angle θₘ 0.9553166181245093 0.95531 66181 245092 78163 Before 1959 false false true true Artin's constant C_Artin 0.37395581361920227 0.37395 58136 19202 28805 Before 1961 Weierstrass constant 0.47494937998792064 0.47494 93799 87920 65033 Before 1978 false false Beam detection constant L 3.1415926535 ≤ L ≤ 4.7998 Before 1980 Natural density constant of abundant numbers d_A 0.2476171 < dA < 0.2476475 Before 1998 Logarithmic capacity of the unit disk 0.5901702995080481 0.59017 02995 08048 11302 Before 2003 false false true Taniguchi constant C_T 0.6782344919173919 0.67823 44919 17391 97803 Before 2005