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Search: id:A073320
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| A073320 |
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A073259(n)=3: the length of iteration transient leading to n-th composite number equals 3. |
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+0
3
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| 4, 5, 8, 9, 13, 16, 17, 18, 22, 23, 24, 27, 31, 35, 36, 40, 41, 46, 47, 56, 64, 69, 70, 71, 89, 90, 91, 92, 93, 94, 95, 103, 109, 110, 111, 112, 113, 146, 147, 161, 162, 163, 171, 172, 173, 174, 196, 240, 241, 242, 243, 261, 262, 263, 277, 438, 439, 440, 1137, 1138
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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See Program.
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EXAMPLE
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The sequence is most probable finite and full. a(1)=4: the fixed point list from m=a(1) to composite[m] is: {4,7,9}, the length is 3; last term is a(64)=1142 with transient list {1142,1332,1360}.
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MATHEMATICA
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lfp[x_] := Length[FixedPointList[x+PrimePi[ # ]+1&, x]]-1 Do[s=lfp[n]; If[Equal[s, 3], Print[n]], {n, 1, 10000000}]
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CROSSREFS
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Cf. A002808, A073259.
Sequence in context: A128217 A042948 A126001 this_sequence A020668 A020934 A094004
Adjacent sequences: A073317 A073318 A073319 this_sequence A073321 A073322 A073323
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KEYWORD
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fini,full,nonn
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AUTHOR
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Labos E. (labos(AT)ana.sote.hu), Jul 29 2002
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