This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A189824 #21 Jun 28 2025 19:45:37 %S A189824 2,5,1,1,8,8,6,4,3,1,5,0,9,5,8,0,1,1,1,0,8,5,0,3,2,0,6,7,7,9,9,3,2,7, %T A189824 3,9,4,1,5,8,5,1,8,1,0,0,7,8,2,4,7,5,4,2,8,6,7,9,8,8,8,4,2,0,9,0,8,2, %U A189824 4,3,2,4,7,7,2,3,5,6,1,3,0,8,4,5,3,8,5,1,0,0,8,8,7,7,7,9,6,9,5,9,1,9,1,6,9 %N A189824 Decimal expansion of Pogson's ratio 100^(1/5). %C A189824 Ratio appearing in the definition of the astronomical magnitude (brightness) scale. %C A189824 Named after the English astronomer Norman Robert Pogson (1829-1891). - _Amiram Eldar_, Apr 24 2021 %H A189824 G. C. Greubel, <a href="/A189824/b189824.txt">Table of n, a(n) for n = 1..10000</a> %H A189824 Norman Pogson, <a href="https://doi.org/10.1093/mnras/17.1.12">Magnitudes of Thirty-Six of the Minor Planets for the First Day of Each Month of the Year 1857</a>, Monthly Notices of the Royal Astronomical Society, Vol. 17, No. 1 (1856), pp. 12-15. %H A189824 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PogsonsRatio.html">Pogson's Ratio</a>. %e A189824 2.511886431509580111085032067799... %t A189824 First[RealDigits[100^(1/5), 10, 200]] %o A189824 (PARI) 10^.4 \\ _Charles R Greathouse IV_, Jan 15 2015 %o A189824 (Magma) 10^(2/5); // _G. C. Greubel_, Jan 14 2018 %K A189824 nonn,easy,cons %O A189824 1,1 %A A189824 _Eric W. Weisstein_, Apr 28 2011