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 A069836 #3 Apr 25 2016 12:05:00 %S A069836 1,4,2,13,3,7,40,22,5,10,6,12,121,31,8,67,9,16,17,364,11,19,202,37,94, %T A069836 49,14,24,15,25,1093,58,112,28,18,27,52,607,20,283,21,34,32,76,23,148, %U A069836 62,73,157,85,26,175,38,43,3280,337,29,46,30,42,850,103,82,45,33,1822 %N A069836 Inverse permutation to A057033: a(n) is the m such that A057033(m) = n, or 0 if no such m exists. %C A069836 Are there any 0's in this sequence? I have computed that the first 1000 terms are all positive, the largest of these being a(980) = 1328602. %e A069836 a(4) = 13 because A057033(13) = 4. %o A069836 (MATLAB) function n = back_cyclic(n) i = 1; while i < n i = i + 1; if mod(n, i) == 0 n = n + i - 1; else n = n - 1; end end %Y A069836 Cf. A057033. %K A069836 easy,nonn %O A069836 1,2 %A A069836 _David Wasserman_, Apr 23 2002