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A162310 The count of lesser-twin-primes smaller than the n-th isolated prime. 0
0, 4, 5, 6, 6, 7, 8, 8, 8, 8, 10, 10, 10, 12, 12, 12, 12, 15, 15, 16, 17, 17, 17, 18, 19, 19, 20, 20, 20, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 25, 25, 25, 25, 26, 26, 26, 27, 27, 28, 29, 29, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The count of members of A001359 smaller than A007510(n).

LINKS

Table of n, a(n) for n=1..72.

EXAMPLE

a(1)=0 because there is no twin prime smaller than 2.

a(2)= 4 counts the numbers 3, 5, 11, and 17 all smaller than 23.

a(3) = 5 counts the numbers 3, 5, 11, 17, and 29 all smaller than 37.

CROSSREFS

Cf. A000040, A141468, A073425.

Sequence in context: A273227 A319500 A022911 * A116962 A273777 A023846

Adjacent sequences:  A162307 A162308 A162309 * A162311 A162312 A162313

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jul 01 2009

EXTENSIONS

Entried checked by R. J. Mathar, Sep 23 2009

STATUS

approved

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Last modified January 24 10:52 EST 2020. Contains 331193 sequences. (Running on oeis4.)