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%I #9 Oct 10 2019 11:51:01
%S 1,2,3,5,20,26,31,483631,225372046,17570301566444363246,
%T 17570301566489340929,
%U 16272673148565174391333181067098727985892644426731405243329
%N 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).
%e 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.
%t f[l_List] := Append[l, l[[ -1]] + Times @@ Select[l, GCD[ #, Length[l]] == 1 &]];Nest[f, {1}, 13] (* _Ray Chandler_, Jan 06 2007 *)
%Y Cf. A127077.
%K nonn
%O 0,2
%A _Leroy Quet_, Jan 04 2007
%E Extended by _Ray Chandler_, Jan 06 2007
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