A090696 Numbers k such that k^2 - 11 is a prime.

4, 8, 10, 18, 20, 28, 32, 38, 42, 48, 52, 62, 70, 78, 80, 90, 118, 120, 130, 148, 158, 160, 172, 182, 200, 210, 218, 228, 230, 232, 238, 248, 252, 258, 260, 262, 270, 272, 290, 298, 300, 302, 318, 340, 342, 350, 358, 360, 370, 372, 378, 388, 398, 410, 412, 420

Offset

1,1

References

M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988.

Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997.

Links

Daniel Starodubtsev, Table of n, a(n) for n = 1..5000

Formula

a(n) = 2*A091271(n).

Mathematica

Select[Range[4, 1200], PrimeQ[#^2-11]&] (* Vladimir Joseph Stephan Orlovsky, Feb 27 2011*)

Crossrefs

A091272 gives primes, A091273 gives prime index.

Sequence in context: A311008 A311009 A311010 * A048247 A276607 A338312

Adjacent sequences: A090693 A090694 A090695 * A090697 A090698 A090699

Keyword

nonn

Author

Giovanni Teofilatto, Dec 20 2003

Extensions

Extended by Ray Chandler, Dec 27 2003

Status

approved