%I A127077
%S A127077 1,2,4,5,13,78,40638,40703,21206263,11221082003820,
%T A127077 15964509207021745126354079410538220,
%U A127077 15964509207021745126410184714526005
%N A127077 a(1)=1. a(n) = a(n-1) + (product of the earlier terms {among terms a(1)
through a(n-1)} which are coprime to n).
%H A127077 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a>
(listed in lieu of email address)
%e A127077 The terms of the sequence, among terms a(1) through a(5), which are coprime
to 6 are a(1)=1, a(4)=5 and a(5) = 13. So a(6) = a(5) + 1*5*13 =
78.
%t A127077 f[l_List] := Append[l, l[[ -1]] + Times @@ Select[l, GCD[ #, Length[l]
+ 1] == 1 &]];Nest[f, {1}, 15] (*Chandler*)
%Y A127077 Cf. A127078.
%Y A127077 Sequence in context: A078652 A102992 A136563 this_sequence A104549 A000063
A039574
%Y A127077 Adjacent sequences: A127074 A127075 A127076 this_sequence A127078 A127079
A127080
%K A127077 nonn
%O A127077 1,2
%A A127077 Leroy Quet Jan 04 2007
%E A127077 Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Jan 06 2007
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