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%I #6 May 14 2015 02:52:09
%S 1,2,3,4,7,8,15,19,20,27,31,32,47,48,66,72,90,111,115,116,123,127,128,
%T 175,183,187,188,242,245,253,254,384,610,613,614,617,618,624,690,826,
%U 836,862,865,866,869,870,891,922,925,926,929,930,982,985,986,989,990
%N Sum of previous term and preceding divisors.
%H Ivan Neretin, <a href="/A120611/b120611.txt">Table of n, a(n) for n = 1..10000</a>
%F a(1) = 1, a(2) = 2, for n>=2, a(n+1) = a(n) + sum_{1<=k<n, a(k) divides a(n)} a(k).
%t a = {1, 2}; Do[AppendTo[a, Plus @@ Intersection[a, Divisors[a[[-1]]]]], {n, 3, 57}]; a (* _Ivan Neretin_, May 13 2015 *)
%Y Cf. A120610, A007497.
%K nonn
%O 1,2
%A _Franklin T. Adams-Watters_, Jun 16 2006
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