A154686 -id:A154686 - cp's OEIS frontend

A155028 Primes p such that p^3 + 2*p^2 + p + 1 is also prime.

2, 5, 7, 13, 23, 47, 79, 89, 103, 109, 137, 139, 193, 223, 229, 257, 277, 293, 317, 347, 379, 389, 443, 457, 499, 593, 607, 653, 677, 709, 733, 823, 853, 883, 907, 953, 1013, 1033, 1087, 1103, 1117, 1283, 1297, 1307, 1327, 1367, 1409, 1489, 1523, 1549, 1597

Offset: 1

Vincenzo Librandi, Jan 19 2009

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Cf. A154686.

[p: p in PrimesUpTo(1600)| IsPrime(p^3 + 2*p^2 + p + 1)]; // Vincenzo Librandi, Oct 30 2012

Select[Prime[Range[1600]], PrimeQ[(#^3 + 2*#^2 + # + 1)]&] (* Vincenzo Librandi, Oct 30 2012 *)

A115018 Numbers k such that (k+1)*(k+2)^2 + 1 is prime.

Original entry on oeis.org

0, 1, 3, 4, 6, 11, 12, 19, 22, 24, 26, 27, 31, 32, 33, 34, 38, 41, 43, 46, 47, 48, 49, 53, 56, 74, 78, 81, 87, 88, 91, 94, 97, 98, 99, 102, 108, 109, 113, 116, 118, 119, 122, 131, 133, 136, 138, 146, 147, 159, 168, 171, 179, 188, 189, 192, 193, 199

Offset: 1

Parthasarathy Nambi, Feb 23 2006

One less than the entry in A154686 at the same index.

			If k=34 then (k+1)*(k+2)^2 + 1 = 45361 (prime).

Cf. A154686.

[ n: n in [0..500] | IsPrime((n+1)*(n+2)^2 + 1) ]; // Vincenzo Librandi, Jan 31 2011

Select[Range[0, 200], PrimeQ[(# + 1)*(# + 2)^2 + 1] &] (* Stefan Steinerberger, Mar 02 2006 *)

is(n)=isprime((n+1)*(n+2)^2+1) \\ Charles R Greathouse IV, Jun 13 2017

More terms from Stefan Steinerberger, Mar 02 2006

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A155028 Primes p such that p^3 + 2*p^2 + p + 1 is also prime.

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A115018 Numbers k such that (k+1)*(k+2)^2 + 1 is prime.

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