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%I #13 Oct 20 2015 16:05:53
%S 3,8,19,36,67,108,167,234,317,426,553,710,889,1080,1291,1532,1809,
%T 2092,2423,2776,3143,3544,3975,4436,4945,5492,6055,6642,7241,7858,
%U 8567,9306,10079,10876,11735,12612,13531,14498,15489,16520,17583,18670,19823
%N Sum of first n primes whose indices are primes.
%C Partial sums of A006450.
%H Harvey P. Dale, <a href="/A083186/b083186.txt">Table of n, a(n) for n = 1..1000</a>
%F Sum_{k=1..n} prime(prime(k)).
%F a(n) ~ (n log n)^2 / 2. - _Charles R Greathouse IV_, Oct 20 2015
%t Accumulate[Prime[Prime[Range[50]]]] (* _Harvey P. Dale_, Jun 24 2012 *)
%o (PARI) pipsum(n)=s=0; sr=0; for(x=1,n, y=prime(prime(x)); s+=y; print1(s" "); sr+=1.0/y; ); print(); print(sr)
%o (PARI) a(n)=my(i,j,s); forprime(p=2,, if(isprime(i++), s+=p; if(j++==n, return(s)))) \\ _Charles R Greathouse IV_, Oct 20 2015
%o (PARI) first(n)=my(v=vector(n),i,j,s); forprime(p=2,, if(isprime(i++), s+=p; v[j++]=s; if(j==n, return(v)))) \\ _Charles R Greathouse IV_, Oct 20 2015
%Y Cf. A006450, A109790.
%K nonn
%O 1,1
%A _Cino Hilliard_, Jun 01 2003
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