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A127078
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a(0)=1. a(n) = a(n-1) + (product of the earlier terms {among terms a(0) through a(n-1)} which are coprime to n).
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1
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1, 2, 3, 5, 20, 26, 31, 483631, 225372046, 17570301566444363246, 17570301566489340929, 16272673148565174391333181067098727985892644426731405243329
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OFFSET
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0,2
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LINKS
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Table of n, a(n) for n=0..11.
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EXAMPLE
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The terms of the sequence, among terms a(0) through a(5), which are coprime to 6 are a(0)=1 and a(3)=5. So a(6) = a(5) + 1*5 = 31.
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MATHEMATICA
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f[l_List] := Append[l, l[[ -1]] + Times @@ Select[l, GCD[ #, Length[l]] == 1 &]]; Nest[f, {1}, 13] (* Ray Chandler, Jan 06 2007 *)
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CROSSREFS
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Cf. A127077.
Sequence in context: A048826 A321084 A054798 * A184252 A228833 A320950
Adjacent sequences: A127075 A127076 A127077 * A127079 A127080 A127081
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KEYWORD
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nonn
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AUTHOR
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Leroy Quet, Jan 04 2007
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EXTENSIONS
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Extended by Ray Chandler, Jan 06 2007
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STATUS
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approved
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