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 A127078 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). 1
 1, 2, 3, 5, 20, 26, 31, 483631, 225372046, 17570301566444363246, 17570301566489340929, 16272673148565174391333181067098727985892644426731405243329 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS EXAMPLE 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. MATHEMATICA f[l_List] := Append[l, l[[ -1]] + Times @@ Select[l, GCD[ #, Length[l]] == 1 &]]; Nest[f, {1}, 13] (* Ray Chandler, Jan 06 2007 *) CROSSREFS Cf. A127077. Sequence in context: A048826 A321084 A054798 * A184252 A228833 A320950 Adjacent sequences:  A127075 A127076 A127077 * A127079 A127080 A127081 KEYWORD nonn AUTHOR Leroy Quet, Jan 04 2007 EXTENSIONS Extended by Ray Chandler, Jan 06 2007 STATUS approved

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Last modified May 27 21:52 EDT 2020. Contains 334671 sequences. (Running on oeis4.)