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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A082466 Least k>=1 such that n^2+kn-1 and n^2+kn+1 are twin primes. 0
3, 1, 1, 11, 1, 1, 53, 1, 3, 5, 7, 3, 11, 16, 1, 11, 43, 6, 11, 1, 1, 8, 13, 1, 17, 7, 3, 11, 43, 4, 11, 4, 7, 8, 31, 9, 17, 1, 9, 35, 1, 4, 53, 4, 7, 41, 43, 6, 23, 1, 17, 8, 67, 1, 5, 4, 17, 11, 1, 7, 197, 4, 3, 11, 25, 1, 227, 7, 3, 14, 157, 19, 11, 16, 3, 71, 43, 6, 53, 7, 7, 44, 31, 3, 41 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

PROG

(PARI) a(n)=if(n<0, 0, k=1; while(isprime(n^2+k*n+1)*isprime(n^2+k*n-1)==0, s++); k)

CROSSREFS

Sequence in context: A100265 A086766 A078688 * A120270 A113711 A103997

Adjacent sequences:  A082463 A082464 A082465 * A082467 A082468 A082469

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Apr 27 2003

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 17 18:41 EST 2012. Contains 206074 sequences.