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 A014285 a(n) = Sum_{j=1..n} j*prime(j). 11

%I

%S 2,8,23,51,106,184,303,455,662,952,1293,1737,2270,2872,3577,4425,5428,

%T 6526,7799,9219,10752,12490,14399,16535,18960,21586,24367,27363,30524,

%U 33914,37851,42043,46564,51290,56505,61941,67750,73944,80457

%N a(n) = Sum_{j=1..n} j*prime(j).

%H Vincenzo Librandi, <a href="/A014285/b014285.txt">Table of n, a(n) for n = 1..1000</a>

%t Join[{s=2},Table[s+=Prime[n]*n,{n,2,33}]] (* _Vladimir Joseph Stephan Orlovsky_, Dec 30 2010 *)

%t Accumulate[Table[i*Prime[i],{i,40}]] (* _Harvey P. Dale_, Sep 10 2014 *)

%o (MAGMA) [&+[k*NthPrime(k): k in [1..n]]: n in [1..40]]; // _Bruno Berselli_, Apr 30 2011

%o (PARI) {a(n) = sum(j=1,n, j*prime(j))}; \\ _G. C. Greubel_, Jun 18 2019

%o (Sage) [sum(j*nth_prime(j) for j in (1..n)) for n in (1..40)] # _G. C. Greubel_, Jun 18 2019

%Y Partial sums of A033286. - _Michel Marcus_, Jun 18 2019

%K nonn,easy

%O 1,1

%A _N. J. A. Sloane_

%E Offset changed to 1 and six terms added by _Bruno Berselli_, Apr 30 2011

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Last modified August 23 11:47 EDT 2019. Contains 326222 sequences. (Running on oeis4.)