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A267290 Primes of the form 11*k^2-11*k+7. 1
7, 29, 73, 139, 227, 337, 997, 1217, 1459, 1723, 2647, 2999, 3373, 3769, 5573, 6079, 6607, 15473, 17167, 18047, 21787, 22777, 23789, 28057, 29179, 30323, 31489, 36373, 37649, 41609, 45767, 48649, 50123, 56239, 61057, 67789, 71287, 74873, 84223, 88117, 108907, 113329, 117839, 124769, 127123, 129499 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes p == 7 (mod 11) such that (4*p-17)/11 is a square. - Robert Israel, Jan 14 2016

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

k = 3: 11*(3^2) - 11*3 + 7 = 73 (is prime).

MAPLE

select(isprime, [seq(11*i^2-11*i+7, i=1..1000)]); # Robert Israel, Jan 14 2016

MATHEMATICA

Select[Array[11 #^2 - 11 # + 7 &, {112}], PrimeQ] (* Michael De Vlieger, Jan 12 2016 *)

Select[Table[11 n^2 - 11 n + 7, {n, 180}], PrimeQ] (* Vincenzo Librandi, Jan 15 2016 *)

PROG

(PARI) lista(nn) = for (k=1, nn, if (isprime(p=11*k^2-11*k+7), print1(p, ", "))); \\ Michel Marcus, Jan 14 2016

(MAGMA) [a: n in [1..100] | IsPrime(a) where a is 11*n^2-11*n+7]; // Vincenzo Librandi, Jan 15 2016

CROSSREFS

Cf. A141854.

Sequence in context: A176616 A231988 A141854 * A079796 A242727 A229795

Adjacent sequences:  A267287 A267288 A267289 * A267291 A267292 A267293

KEYWORD

nonn,easy

AUTHOR

Emre APARI, Jan 12 2016

EXTENSIONS

More terms from Michael De Vlieger, Jan 12 2016

STATUS

approved

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Last modified September 27 19:04 EDT 2020. Contains 337388 sequences. (Running on oeis4.)