A143294 Least a(n) such that p(n)*(p(n)+a(n))-1 and p(n)*(p(n)+a(n))+1 are twin primes with p(i)=i-th prime.

1, 1, 1, 53, 7, 11, 43, 11, 13, 43, 11, 17, 1, 53, 43, 67, 1, 197, 227, 157, 11, 53, 31, 1, 17, 1, 53, 49, 23, 73, 17, 1, 13, 179, 19, 269, 47, 311, 97, 67, 13, 17, 67, 11, 157, 59, 41, 11, 253, 53, 187, 79, 137, 157, 67, 133, 211, 11, 83, 67, 53, 13, 59, 7, 17, 703, 47, 17, 109

Offset

1,4

Links

Pierre CAMI, Table of n, a(n) for n = 1..12250

Example

2*(2+1)-1=5, 2*(2+1)+1=7 5 and 7 twin primes, p(1)=2 so a(1)=1
3*(3+1)-1=11, 3*(3+1)=13 11 and 13 twin primes,p(2)=3 so a(2)=1

Crossrefs

Sequence in context: A051320 A232126 A078681 * A143428 A143385 A231426

Adjacent sequences: A143291 A143292 A143293 * A143295 A143296 A143297

Keyword

nonn

Author

Pierre CAMI, Aug 05 2008

Status

approved