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 A076245 #24 Mar 25 2025 23:22:55
%S A076245 1,3,5,7,11,15,17,19,23,29,47,51,53,59,81,83,85,101,103,107,149,163,
%T A076245 167,173,179,191,197,227,251,255,257,263,269,283,293,311,317,347,359,
%U A076245 367,383,389,467,479,487,503,509,557,563,569,587,607,619,643,653,677
%N A076245 Positions of records in A051547.
%C A076245 Observe that both primes and composites (including 15, 51, 81, 85, and 255) occur.
%C A076245 In totients of consecutive terms some prime-factor appears at higher power than in preceding ones: see A076246 and A051451.
%H A076245 Michael De Vlieger, <a href="/A076245/b076245.txt">Table of n, a(n) for n = 1..13256</a> (First 1924 terms from _Vincenzo Librandi_; a(n) <= 10^6.)
%t A076245 With[{s = FoldList[LCM @@ {#1, EulerPhi@ #2} &, Range[700]]}, Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]]] (* _Michael De Vlieger_, Dec 09 2018 *)
%o A076245 (PARI) lista(nn) = {least = 1; print1(1, ", "); for (n=2, nn, nleast = lcm(least, eulerphi(n)); if (nleast > least, print1(n, ", ")); least = nleast;);} \\ _Michel Marcus_, Jul 30 2017
%Y A076245 Cf. A003418, A051451, A051547, A076244.
%K A076245 nonn
%O A076245 1,2
%A A076245 _Labos Elemer_, Oct 08 2002