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A187619 Sum of the differences of the parts in each Goldbach partition of 2n, A187129(n) - A185297(n). 3

%I #23 Apr 30 2021 12:37:05

%S 0,0,2,4,2,8,16,12,20,28,26,32,24,28,32,64,60,24,58,72,86,88,122,116,

%T 78,128,98,108,144,80,202,204,60,184,216,188,226,292,168,196,316,260,

%U 168,376,236,216,334,120,304,408,278,340,472,392,454,604,452,372,724,216,330,580,162,472,542,392,366,540,470,592,838,384,390,828

%N Sum of the differences of the parts in each Goldbach partition of 2n, A187129(n) - A185297(n).

%H Vincenzo Librandi, <a href="/A187619/b187619.txt">Table of n, a(n) for n = 2..1000</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Goldbach%27s_conjecture">Goldbach's conjecture</a>

%H <a href="/index/Go#Goldbach">Index entries for sequences related to Goldbach conjecture</a>

%F a(n) = 2 * Sum_{i=2..n} (n-i) * A064911(2*n*i-i^2). - _Wesley Ivan Hurt_, Dec 20 2013

%F a(n) = 2 * Sum_{i=3..n} c(i) * c(2*n-i) * (n-i), where c = A010051. - _Wesley Ivan Hurt_, Dec 17 2016

%p with(numtheory):

%p A279725:=n->2*add( (pi(i)-pi(i-1)) * (pi(2*n-i)-pi(2*n-i-1)) * (n-i), i=3..n):

%p seq(A279725(n), n=1..100); # _Wesley Ivan Hurt_, Dec 17 2016

%t Table[2 Sum[(n - i) Floor[2/PrimeOmega[2 n*i - i^2]], {i, 2, n}], {n, 2, 100}] (* _Wesley Ivan Hurt_, Dec 20 2013 *)

%Y Cf. A226237 (Sum of sums), A045917.

%K nonn

%O 2,3

%A _N. J. A. Sloane_, Mar 12 2011

%E More descriptive name by _Wesley Ivan Hurt_, Dec 20 2013

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Last modified April 19 15:11 EDT 2024. Contains 371794 sequences. (Running on oeis4.)