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A053185 Primes of the form p^2 + p - 1 when p is prime. 5
5, 11, 29, 131, 181, 379, 991, 1721, 2861, 3539, 6971, 8009, 10301, 10711, 17291, 22349, 26731, 32941, 36671, 37441, 39799, 54521, 58321, 69431, 79241, 109891, 122149, 139501, 161201, 175979, 186191, 187921, 202049, 212981, 214831, 249499 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Previous name: Primes produced in A053184.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1200

MATHEMATICA

Select[#^2 + # - 1 &/@Prime[Range[200]], PrimeQ] (* Vincenzo Librandi, Aug 12 2017 *)

PROG

(PARI) isA053185(n)={local(r); r=0; for(i=floor(sqrt(n+1)), ceil(sqrt(n)-1), if(isprime(i) && n==i^2+i-1 && isprime(n), r=1)); r} \\ Michael B. Porter, May 10 2010

(PARI) lista(nn) = forprime(p=2, nn, if (isprime(q=p^2+p-1), print1(q, ", "))); \\ Michel Marcus, Aug 12 2017

(MAGMA) [p: p in PrimesUpTo(600) | IsPrime(p) where p is p^2+p-1]; // Vincenzo Librandi, Aug 12 2017

CROSSREFS

Cf. A053184.

Sequence in context: A100965 A001632 A234511 * A090119 A174922 A088484

Adjacent sequences:  A053182 A053183 A053184 * A053186 A053187 A053188

KEYWORD

easy,nonn

AUTHOR

Enoch Haga, Mar 01 2000

EXTENSIONS

New name from Michel Marcus, Aug 12 2017

STATUS

approved

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Last modified April 26 04:04 EDT 2019. Contains 322469 sequences. (Running on oeis4.)