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A228068 Difference between the number of primes with n digits (A006879) and the difference of consecutive integers nearest to Li(10^n) - Li(2) (see A228067). 5
-1, -3, -5, -7, -21, -92, -209, -415, -947, -1403, -8484, -26675, -70708, -205919, -737729, -2162013, -4741957, -13992966, -77928220, -122866869, -374649610, -1334960954, -5317831008, -9896721062, -38014073661 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The sequence A006879(n) is always < A228067(n) for 1<=n<=25.

The sequence (A228067) yields an average relative difference in absolute value, i.e. <ARD(A228068)> = Average(Abs(A228068(n))/ (A006879(n)) = 1.75492…x10^-2 for 1<=n<=25.

Note that A190802(n)=(Li(10^n)-Li(2)) is not defined for n=0. Its value is set arbitrarily to 0.

LINKS

Table of n, a(n) for n=1..25.

Eric Weisstein's World of Mathematics, Prime Counting Function

Eric Weisstein's World of Mathematics, Logarithmic Integral

FORMULA

a(n) = A006879(n) - A228067(n).

CROSSREFS

Cf. A006880, A006879, A228067, A228066.

Sequence in context: A072002 A217651 A163637 * A182233 A239282 A171015

Adjacent sequences:  A228065 A228066 A228067 * A228069 A228070 A228071

KEYWORD

sign

AUTHOR

Vladimir Pletser, Aug 06 2013

STATUS

approved

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Last modified August 10 16:56 EDT 2020. Contains 336381 sequences. (Running on oeis4.)