|
Search: id:A154419
|
|
|
| A154419 |
|
Primes of the form 20n^2+36n+17 |
|
+0
3
|
|
| 17, 73, 953, 1249, 2377, 2833, 3329, 4441, 8737, 12401, 13417, 15569, 17881, 20353, 21649, 28729, 33457, 36809, 49801, 51817, 62497, 67049, 71761, 74177, 86857, 89513, 100537, 103393, 118273, 121369, 127681
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Also primes of the form 5k^2+18k+17. (Proof: this format implies that k=2n, even, because otherwise 5k^2+18k+17 is even and cannot be prime. So 5k^2+18k+17=20n^2+36n+17.) [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 12 2009]
|
|
FORMULA
|
a(n)=20n^2+36n+17
|
|
EXAMPLE
|
For n=0, a(0)=17; n=1, a(1)=73; n=6, a(6)=953
|
|
CROSSREFS
|
Cf. A017377, A154418
Sequence in context: A145440 A112013 A165691 this_sequence A097223 A063494 A146594
Adjacent sequences: A154416 A154417 A154418 this_sequence A154420 A154421 A154422
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 09 2009
|
|
|
Search completed in 0.002 seconds
|
