%I A110794
%S A110794 1,1,2,4,4,8,6,16,9,15,10,26,13,21,21,30,16,36,18,42,35,34,22,62,28,45,
%T A110794 40,61,28,76,31,67,43,55,48,93,36,61,53,90,40,100,43,85,81,70,46,125,55,
%U A110794 100,67,97,53,116,74,120,73,90,58,183,63,98,104,127,84,136,68,135,90
%N A110794 a(1)=1. a(n) = sum{k=1 to n-1}(number of divisors of a(k) which also
divide n).
%H A110794 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a>
(listed in lieu of email address)
%e A110794 The divisors of the first 5 terms of the sequence are: a(1):1; a(2):1;
a(3):1,2; a(4):1,2,4; a(5):1,2,4. Eight of these divisors divide
6. (These divisors are 1;1;1,2;1,2;1,2.) So a(6) = 8.
%t A110794 a = {1}; Do[AppendTo[a, Sum[Length[Select[Divisors[a[[i]]], Mod[Length[a]
+ 1, # ] == 0 &]], {i, 1, Length[a]}]], {70}]; a - Stefan Steinerberger
(stefan.steinerberger(AT)gmail.com), Oct 16 2007
%Y A110794 Sequence in context: A079890 A065608 A077764 this_sequence A117295 A093820
A095400
%Y A110794 Adjacent sequences: A110791 A110792 A110793 this_sequence A110795 A110796
A110797
%K A110794 nonn
%O A110794 1,3
%A A110794 Leroy Quet Apr 26 2007
%E A110794 More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com),
Oct 16 2007
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