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a(n) = sum of n successive primes after the n-th prime.
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%I #17 Apr 13 2018 14:00:19

%S 3,12,31,60,101,156,223,304,401,510,631,766,923,1090,1265,1470,1687,

%T 1926,2179,2448,2735,3040,3353,3698,4057,4428,4817,5230,5661,6106,

%U 6555,7042,7535,8064,8611,9172,9755,10354,10973,11610,12271,12954,13645

%N a(n) = sum of n successive primes after the n-th prime.

%C The prime number theorem implies that, if q(n) = sum of first n primes, then a(n)/q(n) -> 3 as n -> oo. - _N. J. A. Sloane_, Oct 04 2007

%H Harvey P. Dale, <a href="/A131740/b131740.txt">Table of n, a(n) for n = 1..1000</a>

%e a(4)=60 because 11, 13, 17 and 19 follow the 4th prime, 7, and 11 + 13 + 17 + 19 = 60.

%p a:=proc(n) options operator, arrow; add(ithprime(j),j=n+1..2*n) end proc: seq(a(n),n=1..45); # _Emeric Deutsch_, Oct 20 2007

%t Table[Sum[Prime[n + i], {i, 1, n}], {n, 1, 50}] (* _Stefan Steinerberger_, Oct 07 2007 *)

%t Table[Total[Prime[Range[n+1,2n]]],{n,50}] (* _Harvey P. Dale_, Apr 13 2018 *)

%o (PARI) a(n)=my(t=0);for(i=1,n,t=t+prime(n+i));t \\ _Anders Hellström_, Sep 16 2015

%Y Cf. A007504.

%K nonn

%O 1,1

%A _G. L. Honaker, Jr._, Oct 03 2007

%E More terms from _Stefan Steinerberger_, Oct 07 2007

%E More terms from _Emeric Deutsch_, Oct 20 2007