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%I #20 Mar 22 2024 04:23:29
%S 0,0,2,7,23,38,69,89,133,227,268,397,483,536,632,821,1018,1125,1355,
%T 1511,1633,1890,2077,2406,2906,3150,3263,3509,3680,3960,5026,5319,
%U 5854,6003,6909,7130,7761,8345,8681,9381,9986,10351,11456,11771,12212,12481,14128
%N Sum of all proper divisors of all positive integers <= prime(n).
%C Also sum of all proper divisors of all positive integers <= prime(n)-1.
%C Also zero together with the numbers that are repeated in A244049.
%F a(n) = A244049(A000040(n)-1) = A244049(A000040(n)).
%F a(n) ~ (Pi^2/12 - 1/2) * n^2 * log(n)^2. - _Amiram Eldar_, Mar 22 2024
%o (PARI) a(n) = sum(i=2, prime(n), sigma(i)-i-1); \\ _Michel Marcus_, Sep 29 2014
%Y Cf. A000040, A000203, A048050, A244049, A244578, A244583.
%K nonn
%O 1,3
%A _Omar E. Pol_, Jun 30 2014
%E More terms from _Michel Marcus_, Sep 29 2014
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