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A248697 Primes of the form k+(k+3)^2 where k is a nonnegative integer. 1
17, 53, 107, 179, 269, 503, 647, 809, 1187, 1637, 1889, 2447, 2753, 3779, 4157, 4967, 5399, 5849, 6317, 6803, 7307, 7829, 8369, 10709, 11987, 12653, 13337, 14759, 15497, 16253, 17027, 19457, 26729, 29753, 31859, 32939, 35153, 38609, 42227, 44729, 47303, 52667, 55457, 61253, 65789, 68903, 70487, 72089, 73709, 75347 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes > 3 in A014209. - Klaus Purath, Dec 10 2020

LINKS

Table of n, a(n) for n=1..50.

MAPLE

A248697:=n->`if`(isprime(n+(n+3)^2), n+(n+3)^2, NULL): seq(A248697(n), n=1..5*10^2); # Wesley Ivan Hurt, Oct 11 2014

MATHEMATICA

f[x_] := x + (x + 3)^2;

n = 50; result = {}; counter = 0; number = 0;

While[counter < n,

value = f[number];

If[PrimeQ[value] == True, AppendTo[result, value]; counter = counter + 1];

number = number + 1]; result

Select[Table[n + (n + 3)^2, {n, 0, 300}], PrimeQ] (* Vincenzo Librandi, Oct 12 2014 *)

PROG

(MAGMA) [a: n in [0..250] | IsPrime(a) where a is n^2+7*n+9]; // Vincenzo Librandi, Oct 12 2014

(PARI) for(n=1, 10^3, if(isprime(n^2+7*n+9), print1(n^2+7*n+9, ", "))) \\ Derek Orr, Oct 12 2014

CROSSREFS

Cf. A014209.

Sequence in context: A044500 A142105 A031383 * A180456 A154409 A033213

Adjacent sequences:  A248694 A248695 A248696 * A248698 A248699 A248700

KEYWORD

nonn,easy

AUTHOR

Michael Savoric, Oct 11 2014

STATUS

approved

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Last modified December 7 13:08 EST 2021. Contains 349581 sequences. (Running on oeis4.)