|
| |
|
|
A143834
|
|
Numbers n such that 2n^2-1 is not prime
|
|
1
| |
|
|
1, 5, 9, 12, 14, 16, 19, 20, 23, 26, 27, 29, 30, 31, 32, 33, 35, 37, 40, 44, 47, 48, 51, 53, 54, 55, 57, 58, 60, 61, 65, 66, 67, 68, 70, 71, 72, 74, 75, 77, 78, 79, 82, 83, 84, 86, 88, 89, 90, 93, 94, 96, 97, 99, 100, 101, 103, 104, 105, 106, 107, 110, 111, 114, 116, 117
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| Complement of A066049
|
|
|
MATHEMATICA
| p = 2; a = {}; Do[k = p x^2 - 1; If[PrimeQ[k], NULL, AppendTo[a, x]], {x, 1, 1000}]; a
|
|
|
PROG
| (MAGMA) [n: n in [1..120]| not IsPrime(2*n^2-1)] [From Vincenzo Librandi, Jan 28 2011]
|
|
|
CROSSREFS
| A066436, A066049, A090686, A090684, A143826, A143827, A143828, A143829, A143830, A143831, A143833
Sequence in context: A190691 A135979 A123574 * A102183 A153044 A106635
Adjacent sequences: A143831 A143832 A143833 * A143835 A143836 A143837
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Artur Jasinski (grafix(AT)csl.pl), Sep 02 2008
|
| |
|
|
