%I A129141
%S A129141 1,1,3,5,8,13,15,16,31,19,11,13,15,29,28,39,61,29,19,21,40,97,57,37,41,
%T A129141 26,59,61,29,31,33,53,56,81,121,59,40,97,99,65,92,119,111,86,139,93,73,
%U A129141 76,105,227,109,52,115,151,72,169,185,81,113,89,61,63,110,307,177,100
%N A129141 a(1)=a(2)=1. a(n) = the n-th integer from among those positive integers 
               coprime to (a(n-1)*a(n-2)).
%H A129141 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> 
               (listed in lieu of email address)
%e A129141 a(4)*a(5) = 40. So a(6) = the sixth integer from among those positive 
               integers coprime to 40 (ie, the sixth integer in the sequence 1,3,
               7,9,11,13,17,19,21,23,...). So a(6) = 13.
%p A129141 a[1]:=1: a[2]:=1: for n from 3 to 80 do A:={}: for i from 1 to 500 do 
               if gcd(i,a[n-1]*a[n-2])=1 then A:=A union {i} else fi od: a[n]:=A[n]: 
               od: seq(a[n],n=1..80); - Emeric Deutsch (deutsch(AT)duke.poly.edu), 
               Apr 12 2007
%Y A129141 Cf. A129140.
%Y A129141 Sequence in context: A147880 A020643 A092360 this_sequence A097431 A123929 
               A036715
%Y A129141 Adjacent sequences: A129138 A129139 A129140 this_sequence A129142 A129143 
               A129144
%K A129141 nonn
%O A129141 1,3
%A A129141 Leroy Quet Mar 30 2007
%E A129141 More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Apr 12 2007