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A158288 The number of twin prime pairs in the n-th century. 0
8, 7, 4, 2, 3, 2, 3, 0, 5, 0, 5, 1, 3, 2, 4, 0, 4, 2, 2, 3, 3, 3, 2, 3, 0, 2, 2, 3, 1, 1, 0, 2, 2, 4, 2, 4, 1, 1, 2, 2, 4, 2, 5, 1, 2, 2, 2, 2, 0, 2, 2, 0, 2, 0, 3, 2, 3, 1, 3, 0, 1, 2, 1, 1, 1, 2, 2, 4, 2, 2, 0, 1, 1, 3, 2, 3, 0, 1, 1, 1, 2, 0, 3, 1, 1, 2, 1, 0, 3, 1, 2, 0, 2, 1, 4, 0, 2, 2, 1, 1, 4, 1, 1, 2, 2 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

PROG

(PARI) a(n)=my(s=0); forprime(p=100*n-99, 100*n-2, if(isprime(p+2), s++)); s

CROSSREFS

Cf. A001359.

Sequence in context: A086253 A094883 A131081 * A193716 A196914 A072102

Adjacent sequences:  A158285 A158286 A158287 * A158289 A158290 A158291

KEYWORD

nonn

AUTHOR

Ki Punches (ki1212(AT)pocketmail.com), Mar 15 2009

EXTENSIONS

Corrected by Ray Chandler (rayjchandler(AT)sbcglobal.net), May 23 2009

Program from Charles R Greathouse IV (charles.greathouse(AT)case.edu), Feb 03 2011

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.