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 A073323 #9 Nov 23 2024 01:37:58
%S A073323 0,0,4,1,29,153,4913,73114,1985627,69912446,2734947158
%N A073323 Smallest k such that A073259(k)=n or 0 if there is no such value; the first number of which length of fixed-point-list terminated by k-th composite number equals n.
%C A073323 Occurrences of lengths [1-10] for n<=10000000 are {0,0,64,4662,310495,6468633,3041909,173579,658,0}.
%F A073323 a(n) = Min{k: A073259(k)=n}
%e A073323 For lengths n=3, 4, 5, 6, 7, 8 the corresponding lists are: {4, 7, 9}, {1, 2, 3, 4}, {29, 40, 42, 43, 44}, {153, 190, 196, 198, 199, 200}, {4913, 5570, 5649, 5656, 5658, 5659, 5660} and {73114, 80343, 80982, 81039, 81046, 81048, 81049, 81050}.
%t A073323 lfp[x_] := Length[FixedPointList[x + PrimePi[ # ] + 1 &, x]]-1 t=Table[0, {15}]; Do[s=lfp[n]; If[s<16&&t[[s]]==0, t[[s]]=n], {n, 1, 100000}]; t
%Y A073323 Cf. A002808, A073259, A073320-A073322.
%K A073323 more,nonn
%O A073323 1,3
%A A073323 _Labos Elemer_, Jul 29 2002
%E A073323 a(10)-a(11) from _Sean A. Irvine_, Nov 22 2024