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 A031287 #23 Apr 28 2020 05:57:08
%S A031287 0,11,31,51,71,91,111,131,151,171,191,192,194,197,200,203,206,209,212,
%T A031287 215,218,222,252,282,312,342,372,402,432,462,491,492,494,497,500,503,
%U A031287 506,509,512,515,518,522,552,582,612,642,672,702
%N A031287 Position of n-th 0 in A007376.
%C A031287 A007376(a(n)) = 0;
%C A031287 a(n) = Max{A031287(n), A031288(n), A031289(n), A031290(n), A031291(n), A031292(n), A031293(n), A031294(n), A031295(n), A031296(n)}. [_Reinhard Zumkeller_, Jul 28 2011]
%H A031287 Reinhard Zumkeller, <a href="/A031287/b031287.txt">Table of n, a(n) for n = 1..10001</a> [a(1)=0 inserted by _Georg Fischer_, Apr 28 2020]
%o A031287 (Haskell)
%o A031287 import Data.List (elemIndices)
%o A031287 a031287 n = a031287_list !! (n-1)
%o A031287 a031287_list = map (+ 1) $ elemIndices 0 a007376_list
%o A031287 -- _Reinhard Zumkeller_, Jul 28 2011
%Y A031287 Cf. A193428.
%K A031287 nonn,less,base,look
%O A031287 1,2
%A A031287 _Clark Kimberling_
%E A031287 a(1)=0 inserted for consistency with change in A007376 by _Sean A. Irvine_, Apr 21 2020