%I A064946
%S A064946 0,2,3,10,5,26,7,34,21,42,11,104,13,58,58,98,17,152,19,165,80,90,23,
%T A064946 324,55,106,102,227,29,397,31,258,124,138,124,575,37,154,146,507,41,
%U A064946 544,43,351,325,186,47,892,105,392,190,413,53,692,192,693,212,234,59
%N A064946 Sum_{i|n, j|n, j>i} j.
%H A064946 Harry J. Smith, <a href="b064946.txt">Table of n, a(n) for n=1,...,1000</
a>
%F A064946 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 A064946 a(6) = dot_product(0,1,2,3)*(1,2,3,6)=0*1+1*2+2*3+3*6=26.
%p A064946 with(numtheory): seq(add((i-1)*sort(convert(divisors(n),'list'))[i],i=1..tau(n)),
n=1..200);
%o A064946 (PARI) { for (n=1, 1000, d=divisors(n); a=sum(i=2, length(d), (i - 1)*d[i]);
write("b064946.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net),
Oct 01 2009]
%Y A064946 Cf. A000005, A000203.
%Y A064946 Sequence in context: A048985 A112417 A139693 this_sequence A078730 A163767
A128531
%Y A064946 Adjacent sequences: A064943 A064944 A064945 this_sequence A064947 A064948
A064949
%K A064946 nonn
%O A064946 1,2
%A A064946 Vladeta Jovovic (vladeta(AT)eunet.rs), Oct 28 2001
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