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 A061568 Number of primes <= sum of first n primes. 3
 1, 3, 4, 7, 9, 13, 16, 21, 25, 31, 37, 45, 51, 60, 66, 75, 85, 95, 103, 115, 127, 138, 150, 162, 177, 191, 205, 219, 233, 250, 267, 283, 300, 319, 338, 360, 376, 400, 421, 441, 461, 481, 509, 531, 557, 578, 602, 630, 653, 684, 707, 737, 765, 793, 825, 853, 884 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Harry J. Smith, Table of n, a(n) for n = 1..1000 FORMULA a(n) = A000720(A007504(n)). - Michel Marcus, Jul 02 2018 MATHEMATICA PrimePi/@FoldList[Plus, 0, Prime[Range[50]]]//Rest PROG (PARI) { default(primelimit, 3682913); n=0; s=0; forprime (p=2, prime(1000), s+=p; write("b061568.txt", n++, " ", primepi(s)) ) } \\ Harry J. Smith, Jul 24 2009 (PARI) a(n) = primepi(sum(k=1, n, prime(k))); \\ Michel Marcus, Jul 02 2018 CROSSREFS Cf. A000849, A000720, A007504. Sequence in context: A072441 A152032 A004652 * A146994 A330146 A295069 Adjacent sequences:  A061565 A061566 A061567 * A061569 A061570 A061571 KEYWORD easy,nonn AUTHOR Harvey P. Dale, May 18 2001 STATUS approved

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Last modified January 20 08:32 EST 2022. Contains 350467 sequences. (Running on oeis4.)