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Search: id:A102448
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%I A102448
%S A102448 1,0,0,1,0,0,0,0,1,0,0,0,0,0,0,1,0,1,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,
%T A102448 1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,
%U A102448 0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,2,0,0,0,0,0
%N A102448 a(n) = number of ways to write n = k^2 * j, j <= k, GCD(k,j) = 1, j and 
               k = positive integers.
%C A102448 Sum_{n>0} a(n)/n = 2.
%H A102448 Leroy Quet, <a href="http://www.prism-of-spirals.net/">Home Page</a> 
               (listed in lieu of email address)
%e A102448 a(18) = 1 because 18 = k^2 * j, j <= k, GCD(k,j)=1, in one way: k=3, 
               j=2.
%t A102448 t = Sort[ Flatten[ Table[ If[ GCD[j, k] == 1, k^2*j, {}], {k, 11}, {j, 
               k}]]]; Table[ Count[t, n], {n, 105}] (from Robert G. Wilson v Feb 
               25 2005)
%Y A102448 Cf. A102354, A104021, A104023, A104025.
%Y A102448 Sequence in context: A118626 A062892 A118553 this_sequence A102683 A122840 
               A083919
%Y A102448 Adjacent sequences: A102445 A102446 A102447 this_sequence A102449 A102450 
               A102451
%K A102448 nonn
%O A102448 1,100
%A A102448 Leroy Quet, Feb 23 2005
%E A102448 More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 24 2005

    
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Last modified December 1 13:27 EST 2009. Contains 167806 sequences.


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