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Length of FixedPointList leading to value of [10^n]-th composite number.
1

%I #8 Aug 29 2019 05:23:02

%S 4,4,4,5,5,6,7,7,7,8,8,9,9

%N Length of FixedPointList leading to value of [10^n]-th composite number.

%C One plus the number of iterations necessary to reach the composite number using the formula in the program. - _Robert G. Wilson v_, Jul 23 2002

%F See program below.

%e n=10^11: the list= {100000000000, 104118054814, 104280509328, 104286914053, 104287166025, 104287176027, 104287176414, 104287176419}, its length including initial term is 8, so a(11)=8.

%t Table[Length[FixedPointList[10^w+PrimePi[ # ]+1&, 10^w]]-1, {w, 1, 11}]

%Y Cf. A064814, A065857, A002808, A073255-A073264.

%K nonn,more

%O 1,1

%A _Labos Elemer_, Jul 22 2002

%E More terms from _Robert G. Wilson v_, Jul 23 2002