A121068 -id:A121068 - cp's OEIS frontend

A201704 Primes of the form 8*k^2 + 7.

7, 79, 5839, 7207, 8719, 18439, 25999, 28807, 41479, 45007, 48679, 93319, 109519, 121039, 145807, 180007, 209959, 294919, 313639, 342799, 415879, 472399, 583207, 720007, 734479, 778759, 935719, 952207, 1216807, 1331719, 1391119, 1431439

Offset: 1

Vincenzo Librandi, Dec 04 2011

Vincenzo Librandi, Table of n, a(n) for n = 1..5000

Cf. A121068 (corresponding k).

[a: n in [0..500] | IsPrime(a) where a is 8*n^2+7];

Mathematica
```
Select[Table[8n^2+7,{n,0,200}],PrimeQ]
```

A121089 Numbers n such that f(n), f(n+1) and f(n+2) are prime, f(m)=72*m^2+7.

Original entry on oeis.org

9, 24, 169, 1479, 2964, 3039, 3299, 4084, 4474, 5534, 5574, 6449, 7359, 7409, 7529, 10789, 10879, 10994, 13819, 14324, 18574, 19709, 20329, 20749, 22179, 24529, 25089, 25104, 25229, 25404, 27714, 27779, 29849, 30234, 32369, 33384, 34799

Offset: 1

Zak Seidov, Aug 11 2006

nonn

Apparently there are no four subsequent numbers m with f(m) prime.

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Cf. A007522, A121068.

Reap[Do[If[PrimeQ[72*n^2+7]&&PrimeQ[72*(n+1)^2+7]&&PrimeQ[72*(n+2)^2+7],Sow[n]],{n,0,300000}]][[2,1]]
Flatten[Position[Partition[Table[PrimeQ[72n^2+7],{n,35000}],3,1],{True,True,True}]] (* Harvey P. Dale, Aug 17 2014 *)

cp's OEIS Frontend

A201704 Primes of the form 8*k^2 + 7.

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