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%I #9 Jun 19 2018 05:17:06
%S 0,2,3,10,5,26,7,34,21,42,11,104,13,58,58,98,17,152,19,165,80,90,23,
%T 324,55,106,102,227,29,397,31,258,124,138,124,575,37,154,146,507,41,
%U 544,43,351,325,186,47,892,105,392,190,413,53,692,192,693,212,234,59
%N a(n) = Sum_{i|n, j|n, j>i} j.
%H Harry J. Smith, <a href="/A064946/b064946.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = Sum_{i=1..tau(n)} (i-1)*d_i, where {d_i}, i=1..tau(n), is increasing sequence of divisors of n.
%e a(6) = dot_product(0,1,2,3)*(1,2,3,6) = 0*1 + 1*2 + 2*3 + 3*6 = 26.
%p with(numtheory): seq(add((i-1)*sort(convert(divisors(n),'list'))[i],i=1..tau(n)), n=1..200);
%o (PARI) { for (n=1, 1000, d=divisors(n); a=sum(i=2, length(d), (i - 1)*d[i]); write("b064946.txt", n, " ", a) ) } \\ _Harry J. Smith_, Oct 01 2009
%Y Cf. A000005, A000203.
%K nonn
%O 1,2
%A _Vladeta Jovovic_, Oct 28 2001
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