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A127010
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a(0)=1. a(n) = the numerator of the sum of the reciprocals of the earlier terms of the sequence which are coprime to n.
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1
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1, 1, 2, 5, 11, 57, 126, 17609, 127439468, 344473534513077, 891027683693605833852, 156052046552117500148945259643265853536683707838813
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,3
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EXAMPLE
| The sequence's terms, among terms a(0) through a(5), which are coprime to 6 are a(0)=1,a(1)=1,a(3)=5 and a(4)=11. So a(6) is the numerator of 1 +1 +1/5 +1/11 = 126/55, which is 126.
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MATHEMATICA
| f[l_List] := Sum[1/l[[k]], {k, Length[l]}]; g[l_List] := Block[{n = Length[l]}, Append[l, Numerator@f[Select[l, GCD[ #, n] == 1 &]]]]; Nest[g, {1}, 12] (*Chandler*)
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CROSSREFS
| Cf. A127009.
Sequence in context: A106887 A089609 A087185 * A140547 A131480 A018847
Adjacent sequences: A127007 A127008 A127009 * A127011 A127012 A127013
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KEYWORD
| nonn
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AUTHOR
| Leroy Quet Jan 02 2007
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EXTENSIONS
| Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Jan 04 2007
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