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%I #30 Sep 20 2022 11:01:37
%S 4,15,50,119,308,533,986,1463,2300,3741,4960,7289,9758,12083,15416,
%T 20193,25960,30561,38056,45369,51976,62489,72542,85707,102820,117261,
%U 130192,146697,161320,180009,218440,242481,272356,295653,339124,366477
%N a(n) = prime(n) * Sum_{i=1..n} prime(i).
%C Row sums of triangle A087112.
%C Sum of semiprimes (A001358) with greater prime factor prime(n). - _Gus Wiseman_, Dec 06 2020
%H Reinhard Zumkeller, <a href="/A143215/b143215.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A000040(n) * A007504(n).
%e The series begins (4, 15, 50, 119, 308,...) since the primes = (2, 3, 5, 7, 11,...) and partial sum of primes = (2, 5, 10, 17, 28,...).
%e a(5) = 308 = 11 * 28.
%e a(4) = 119 = sum of row 4 terms of triangle A087112: (14 + 21 + 35 + 49).
%p A143215:=n->ithprime(n)*sum(ithprime(i), i=1..n); seq(A143215(n), n=1..50); # _Wesley Ivan Hurt_, Mar 26 2014
%t Table[Prime[n]*Sum[Prime[i], {i, n}], {n, 50}] (* _Wesley Ivan Hurt_, Mar 26 2014 *)
%o (Haskell)
%o a143215 n = a000040 n * a007504 n -- _Reinhard Zumkeller_, Nov 25 2012
%Y Cf. A007504.
%Y Row sums of A087112.
%Y The squarefree version is A339194, row sums of A339116.
%Y Semiprimes grouped by weight are A338904, with row sums A024697.
%Y Squarefree semiprimes grouped by weight are A338905, with row sums A025129.
%Y Squarefree numbers grouped by greatest prime factor are A339195, with row sums A339360.
%Y A001358 lists semiprimes.
%Y A006881 lists squarefree semiprimes.
%Y A332765 is the greatest semiprime of weight n.
%Y A338898/A338912/A338913 give the prime indices of semiprimes.
%Y A338899/A270650/A270652 give the prime indices of squarefree semiprimes.
%Y Cf. A000040, A001222, A001748, A014342, A098350, A100484, A168472, A319613, A339003, A339114/A339115.
%K nonn
%O 1,1
%A _Gary W. Adamson_, Jul 30 2008
%E More terms from _Vladimir Joseph Stephan Orlovsky_, Sep 21 2009
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