login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A000885 Number of twin prime pairs < square of n-th prime. 2
0, 2, 4, 6, 10, 12, 19, 21, 25, 33, 35, 46, 53, 56, 67, 80, 93, 98, 117, 128, 131, 146, 160, 174, 195, 210, 217, 227, 233, 244, 286, 298, 325, 331, 376, 386, 406, 423, 444, 467, 492, 505, 554, 561, 581, 589, 641, 700, 723, 732, 748, 780, 789, 835, 868, 895, 938, 945, 975 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..10000

MATHEMATICA

With[{tpps=Select[Partition[Prime[Range[10000]], 2, 1], Last[#]- First[#] == 2&]}, Table[ Count[tpps, _?(Last[#]<Prime[n]^2&)], {n, 60}]] (* From Harvey P. Dale, Aug 11 2011 *)

CROSSREFS

Cf. A000879.

Sequence in context: A055235 A083887 A064374 * A068336 A194944 A133871

Adjacent sequences:  A000882 A000883 A000884 * A000886 A000887 A000888

KEYWORD

nonn

AUTHOR

gandalf(AT)hrn.office.ssi.net (James D. Ausfahl)

EXTENSIONS

More terms from David W. Wilson (davidwwilson(AT)comcast.net)

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 15 21:10 EST 2012. Contains 205856 sequences.