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%I #5 Oct 15 2013 22:31:26
%S 0,0,4,1,29,153,4913,73114,1985627
%N Smallest x such that A073259[x]=n; the first number of which length of fixed-point-list terminated by x-th composite number equals n.
%C Occurrences of lengths [1-10] for n<=10000000 are {0,0,64,4662,310495,6468633,3041909,173579,658,0}.
%F a(n)=Min{x; A073259[x]=n}
%e 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 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 Cf. A002808, A073259, A073320-A073322.
%K more,nonn
%O 1,3
%A _Labos Elemer_, Jul 29 2002
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