%I #8 Mar 06 2016 07:39:05
%S 1,4,5,6,7,8,9,10,11,12,13,14,15,16,17,19,20,21,23,24,25,27,29,31,32,
%T 35,36,37,39,41,44,45,47,49,51,55,56,57,59,60,65,67,69,71,72,77,79,80,
%U 81,84,85,87,91,92,95,99,101,104,105,107
%N a(n) = least positive integer < a(n-1) and not a(i)*a(j)-2 for 1<=i<j<=n.
%H Ivan Neretin, <a href="/A026456/b026456.txt">Table of n, a(n) for n = 1..1000</a>
%t a = {1, 4}; used = {a[[1]]*a[[2]] - 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; used = Union[used, k*a - 2]; AppendTo[a, k], {n, 3, 60}]; a (* _Ivan Neretin_, Mar 06 2016 *)
%Y Cf. A026453 and references therein.
%K nonn
%O 1,2
%A _Clark Kimberling_
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