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A146214 a(n) = 10^n-th lower twin prime. 3
3, 107, 3821, 79559, 1260989, 18409199, 252427601, 3285916169, 41375648687, 507575862527, 6100479510551 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The Gcc with Gmp program is at the bottom of the link. The link also has a PARI bisection algorithm which gives a very good approximation for the n-th prime number and the n-th twin prime number. For example the 10^10-th lower twin prime approximation is 6100475249386, this has a relative error of 0.000000698... from the actual a(10) above.

The 10^n-th upper twin prime is given as a(n)+2 = (5,109,3823,79561, 1260991,18409201,252427603,...). - M. F. Hasler, Dec 06 2008

LINKS

Table of n, a(n) for n=0..10.

Cino Hilliard, Approximating the n-th lower twin prime (broken link)

FORMULA

a(n) = A001359(10^n). - M. F. Hasler, Dec 06 2008

EXAMPLE

The first 10 lower twin primes are: 3,5,11,17,29,41,59,71,101,107. So 107 is the 10th lower twin prime.

CROSSREFS

Cf. A001097, A147797.

Sequence in context: A023325 A094200 A003705 * A261997 A061308 A302060

Adjacent sequences:  A146211 A146212 A146213 * A146215 A146216 A146217

KEYWORD

nonn,more

AUTHOR

Cino Hilliard, Oct 28 2008

EXTENSIONS

a(0) from Zak Seidov, Oct 29 2008

Edited and cross-references added by M. F. Hasler, Dec 06 2008

STATUS

approved

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Last modified July 23 11:44 EDT 2019. Contains 325254 sequences. (Running on oeis4.)