|
| |
|
|
A072570
|
|
Even interprimes i = (p+q)/2 (where p, q are consecutive primes) such that (q-p)/2 is not divisible by 3.
|
|
2
| |
|
|
4, 6, 12, 18, 30, 42, 60, 72, 102, 108, 120, 138, 144, 150, 180, 186, 192, 198, 228, 240, 246, 270, 282, 288, 300, 312, 324, 342, 348, 414, 420, 426, 432, 462, 522, 552, 570, 582, 600, 618, 636, 642, 660, 696, 714, 780, 792, 810, 816, 822, 828, 834, 846, 858
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| A superset of A014574. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Mar 03 2009]
|
|
|
FORMULA
| d = (P_n+1 - P_n)/2 is even & d == +/- 1 (mod 6).
|
|
|
MATHEMATICA
| a = Table[Prime[n], {n, 2, 200}]; b = {}; Do[d = (a[[n + 1]] - a[[n]])/2; If[ EvenQ[ a[[n]] + d] && (Mod[d, 6] == 5 || Mod[d, 6] == 1), b = Append[b, a[[n]] + d]], {n, 1, 198}]; b
|
|
|
CROSSREFS
| Cf. A024675, A072571. A072568 is union of A072571 and this sequence.
Sequence in context: A068570 A074998 A061715 * A014574 A034425 A073123
Adjacent sequences: A072567 A072568 A072569 * A072571 A072572 A072573
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Marco Matosic (marcomatosic(AT)hotmail.com), Jun 24 2002
|
|
|
EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com) and Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 27 2002
|
| |
|
|
