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 A143215 a(n) = prime(n) * sum(i=1..n, prime(i) ). 2
 4, 15, 50, 119, 308, 533, 986, 1463, 2300, 3741, 4960, 7289, 9758, 12083, 15416, 20193, 25960, 30561, 38056, 45369, 51976, 62489, 72542, 85707, 102820, 117261, 130192, 146697, 161320, 180009, 218440, 242481, 272356, 295653, 339124, 366477 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row sums of triangle A087112. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 FORMULA a(n) = A000040(n) * A007504(n). EXAMPLE 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,...). a(5) = 308 = 11 * 28. a(4) = 119 = sum of row 4 terms of triangle A087112: (14 + 21 + 35 + 49). MAPLE A143215:=n->ithprime(n)*sum(ithprime(i), i=1..n); seq(A143215(n), n=1..50); # Wesley Ivan Hurt, Mar 26 2014 MATHEMATICA Table[Prime[n]*Sum[Prime[i], {i, n}], {n, 50}] (* Wesley Ivan Hurt, Mar 26 2014 *) PROG (Haskell) a143215 n = a000040 n * a007504 n  -- Reinhard Zumkeller, Nov 25 2012 CROSSREFS Cf. A000040, A007504, A087112. Sequence in context: A056337 A053406 A225265 * A301973 A132308 A026110 Adjacent sequences:  A143212 A143213 A143214 * A143216 A143217 A143218 KEYWORD nonn AUTHOR Gary W. Adamson, Jul 30 2008 EXTENSIONS More terms from Vladimir Joseph Stephan Orlovsky, Sep 21 2009 STATUS approved

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Last modified January 26 23:05 EST 2020. Contains 331289 sequences. (Running on oeis4.)