|
| |
|
|
A129926
|
|
Semiprimes n such that 3*n - 2 is a prime.
|
|
1
| |
|
|
15, 21, 25, 33, 35, 51, 55, 65, 77, 91, 93, 95, 111, 123, 133, 141, 145, 155, 183, 201, 203, 205, 215, 221, 237, 247, 253, 287, 295, 303, 323, 341, 355, 365, 377, 391, 411, 413, 417, 427, 485, 497, 511, 515, 517, 527, 533, 537, 543, 553, 565, 581, 583, 597
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Indices of 3-almost prime octagonal numbers.
Subset of A001358. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 07 2007
|
|
|
MAPLE
| isA001358 := proc(n) if numtheory[bigomega](n) = 2 then true ; else false ; end ; end: isA129926 := proc(n) if isA001358(n) then isprime(3*n-2) ; else false ; fi ; end: for n from 1 to 1000 do if isA129926(n) then printf("%d, ", n) ; fi ; od ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 07 2007
|
|
|
CROSSREFS
| Sequence in context: A154545 A156063 A181780 * A020204 A057489 A070811
Adjacent sequences: A129923 A129924 A129925 * A129927 A129928 A129929
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Giovanni Teofilatto (g.teofilatto(AT)tiscalinet.it), Jun 06 2007
|
|
|
EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 07 2007
|
| |
|
|
