The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A247882 Numbers, p, that generate the prime quadruplets p^2-2p+2k (for k = -2, -1, 1, 2). 1
 5, 15, 705, 2795, 14105, 18645, 38547, 43485, 53915, 57957, 62417, 76287, 82355, 94445, 96657, 145937, 162605, 178817, 180677, 184877, 193625, 234017, 238887, 256557, 261017, 287835, 297815, 334007, 339525, 346425, 387297, 399387, 407145, 417597, 418845, 419147 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS For a subset of this list, restricted only to primes, see A247845. LINKS EXAMPLE 5 is in the sequence as it generates the prime quadruplet 5^2-2*5-4=11; 5^2-2*5-2=13; 5^2-2*5+2=17; and, 5^2-2*5+4=19. PROG (PARI) lista(nn) = {vk = [-2, -1, 1, 2]; for (p = 2, nn, nb = 0; for (k = 1, 4, nb += isprime(p^2-2*p+2*vk[k]); ); if (nb == 4, print1(p, ", ")); ); } \\ Michel Marcus, Sep 26 2014 CROSSREFS Cf. A247845 (subsequence of primes). Sequence in context: A112273 A298510 A318898 * A215901 A112515 A001141 Adjacent sequences:  A247879 A247880 A247881 * A247883 A247884 A247885 KEYWORD nonn AUTHOR Ray G. Opao, Sep 25 2014 EXTENSIONS More terms from Michel Marcus, Sep 26 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 7 06:02 EDT 2020. Contains 336274 sequences. (Running on oeis4.)