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 A364198 #14 Jul 23 2023 02:08:39 %S A364198 0,1,3,6,11,16,26,43,69,115,141,158,208,293,358,440,541,642,743,1117, %T A364198 1378,1612,1826,2052,2494,2856,3181,3703,4107,4862,5347,5924,6454, %U A364198 7645,8322,8999,9784,10941,12458,13580,14542,15839,16864,18309,19876,21696,23311,25408,28377,30314 %N A364198 Index of first occurrence of n in A364197. %F A364198 a(n) ~ n^3/3 (conjectured). %t A364198 s[0] = 0; s[n_] := s[n] = s[Abs[n - 1 - s[n - 1]^2]] + 1; TakeWhile[Flatten[FirstPosition[Array[s, 32000, 0] , #] & /@ Range[0, 50]] - 1 , NumberQ] (* _Amiram Eldar_, Jul 13 2023 *) %o A364198 (Python) %o A364198 a = [0]; [a.append(a[abs(n-a[n]**2)]+1) for n in range(1000)] # A364197 %o A364198 b = [a.index(n) for n in range(max(a)+1)] # A364198 %Y A364198 Cf. A364197. %K A364198 nonn %O A364198 0,3 %A A364198 _Rok Cestnik_, Jul 13 2023