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 A289152 #7 Jun 29 2017 13:47:00 %S A289152 1,1,1,2,1,3,2,3,4,5,1,6,2,7,3,4,1,8,5,6,7,8,2,9,3,10,11,12,4,13,5,6, %T A289152 7,8,9,14,10,15,11,12,1,16,13,14,15,16,2,17,18,19,3,20,4,17,5,21,22, %U A289152 23,6,24,7,25,26,8,9,27,10,11,12,28,13,29,14,30,15 %N A289152 Ordinal transform of A003434. %C A289152 The ordinal transform mentioned is the one described in A002260: the ordinal transform of a sequence b(n) is the sequence t(n) = number of values in b(1),...,b(n) which are equal to b(n). %C A289152 This sequence has graphical similarities with A286343. %H A289152 Rémy Sigrist, <a href="/A289152/b289152.txt">Table of n, a(n) for n = 1..10000</a> %e A289152 The first terms are: %e A289152 n A003434(n) a(n) %e A289152 -- ---------- ---- %e A289152 1 0 1 %e A289152 2 1 1 %e A289152 3 2 1 %e A289152 4 2 2 %e A289152 5 3 1 %e A289152 6 2 3 %e A289152 7 3 2 %e A289152 8 3 3 %e A289152 9 3 4 %e A289152 10 3 5 %e A289152 11 4 1 %e A289152 12 3 6 %e A289152 13 4 2 %e A289152 14 3 7 %e A289152 15 4 3 %e A289152 16 4 4 %e A289152 17 5 1 %e A289152 18 3 8 %e A289152 19 4 5 %e A289152 20 4 6 %t A289152 With[{nn = 75}, Function[s, Table[Count[#, Last@ #] &@ Take[s, n], {n, nn}]]@ Table[Length@ NestWhileList[EulerPhi, n, # != 1 &] - 1, {n, nn}]] (* _Michael De Vlieger_, Jun 27 2017 *) %o A289152 (PARI) A003434(n) = for (k=0, oo, if (n==1, return (k), n=eulerphi(n))) %o A289152 o = vector(10); for (n=1, 100, v=A003434(n); o[1+v]++; print1(o[1+v] ", ")) %Y A289152 Cf. A002260, A003434, A286343. %K A289152 nonn,look %O A289152 1,4 %A A289152 _Rémy Sigrist_, Jun 26 2017