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A117503 Primes among partial sums of floor(Pi*prime(k)), k=1,2,3,.... 3
613, 6229, 7607, 9679, 46133, 61469, 69191, 120067, 211663, 285049, 316697, 354323, 402371, 444979, 481109, 490313, 532709, 993907, 1055543, 1083721, 1237487, 1329701, 1409977, 1442899, 1484671, 1656199, 1700471, 1874767 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Modeled on the same concept as cumulative sums of squared primes in A098562.

LINKS

Table of n, a(n) for n=1..28.

FORMULA

Define the sequence s as s(j) = Sum_{k=1..j} floor(Pi*prime(k)) for j >= 1; then a(n) is the n-th prime in the sequence s.

MAPLE

Digits := 30 ; A117503 := proc(nmax) local a, pisum, p ; a := [] ; pisum := 0 ; p :=1 ; while nops(a) <=nmax do while true do pisum := pisum+floor(Pi*ithprime(p)) ; p := p+1 ; if isprime(pisum) then a := [op(a), pisum] ; break ; fi ; od : od : RETURN(a) ; end: a := A117503(30) ; # R. J. Mathar, Oct 26 2006

PROG

UBASIC 10 Ct=1 20 B=nxtprm(B) 30 C=int(pi(B)) 40 D=D+C 41 print Ct, B, C, D 50 if D=prmdiv(D) then print D:stop 55 Ct=Ct+1 60 goto 20

CROSSREFS

Cf. A117504, A098562.

Sequence in context: A090869 A020372 A032657 * A165771 A025329 A252608

Adjacent sequences:  A117500 A117501 A117502 * A117504 A117505 A117506

KEYWORD

easy,nonn,less

AUTHOR

Enoch Haga, Mar 25 2006

EXTENSIONS

Edited by Jon E. Schoenfield, Sep 23 2018

STATUS

approved

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Last modified April 21 08:55 EDT 2019. Contains 322328 sequences. (Running on oeis4.)