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A053622 a(n) = round( n/log(n) - pi(n) ). 1
2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, 0, 0, -1, -1, -2, -1, -1, -1, -2, -1, -1, -1, -1, -1, -1, -1, -2, -2, -2, -1, -1, -1, -2, -2, -1, -1, -2, -2, -3, -2, -2, -2, -3, -3, -2, -2, -2, -2, -3, -2, -2, -2, -2, -2, -3, -2, -3, -3, -3, -3, -2, -2, -3, -3, -3, -3, -3, -3 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

G. C. Greubel, Table of n, a(n) for n = 2..1000

C. K. Caldwell, How Many Primes Are There?

FORMULA

a(n) = A050499(n) - A000720(n).

MATHEMATICA

Table[Round[n/Log[n] - PrimePi[n]], {n, 2, 80}] (* G. C. Greubel, Apr 20 2017 *)

PROG

(PARI) vector(80, n, n++; round(n/log(n) - primepi(n)) ) \\ G. C. Greubel, May 17 2019

(MAGMA) [Round(n/Log(n) - #PrimesUpTo(n)): n in [2..80]]; // G. C. Greubel, May 17 2019

(Sage) [round(n/log(n) - prime_pi(n)) for n in (2..80)] # G. C. Greubel, May 17 2019

CROSSREFS

Cf. A000720, A050499, A052434, A052435.

Sequence in context: A270668 A196272 A086073 * A016408 A316868 A106822

Adjacent sequences:  A053619 A053620 A053621 * A053623 A053624 A053625

KEYWORD

sign,changed

AUTHOR

Henry Bottomley, Mar 21 2000

STATUS

approved

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Last modified May 23 20:23 EDT 2019. Contains 323528 sequences. (Running on oeis4.)