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Revision History for A243889

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Showing entries 1-10 | older changes

A243889

Primes of the form 2*n^2+30*n+13.
(history; published version)

#11 by Charles R Greathouse IV at Thu Sep 08 08:46:08 EDT 2022

PROG

(MAGMAMagma) [a: n in [1..800] | IsPrime(a) where a is 2*n^2+30*n+13];

Discussion

Thu Sep 08

08:46

OEIS Server: https://oeis.org/edit/global/2944

#10 by Bruno Berselli at Fri Apr 10 09:26:37 EDT 2015

STATUS

reviewed

approved

#9 by Michel Marcus at Fri Apr 10 09:18:39 EDT 2015

STATUS

proposed

reviewed

#8 by Vincenzo Librandi at Fri Apr 10 08:52:30 EDT 2015

STATUS

editing

proposed

#7 by Vincenzo Librandi at Fri Apr 10 08:52:21 EDT 2015

COMMENTS

2*a(n) + 199 is a square. - Vincenzo Librandi, Apr 10 2015

STATUS

approved

editing

#6 by Bruno Berselli at Wed Jun 18 09:36:18 EDT 2014

STATUS

editing

approved

#5 by Bruno Berselli at Wed Jun 18 09:36:08 EDT 2014

COMMENTS

Subsequence of A142104.

CROSSREFS

Cf. A142104.

STATUS

proposed

editing

#4 by Vincenzo Librandi at Mon Jun 16 02:30:59 EDT 2014

STATUS

editing

proposed

Discussion

Tue Jun 17

12:04

Bruno Berselli: These primes are of the form 18k(k+5)+13. Subsequence of A142104.

#3 by Vincenzo Librandi at Mon Jun 16 02:30:53 EDT 2014

COMMENTS

Conjecture: except 2281, 2^a(n)-1 is not prime; in other words, these primes are included in A054723.

#2 by Vincenzo Librandi at Mon Jun 16 01:36:02 EDT 2014

NAME

allocated for Vincenzo LibrandiPrimes of the form 2*n^2+30*n+13.

DATA

661, 1201, 2281, 2713, 3181, 4801, 5413, 8221, 9013, 12541, 13513, 17761, 18913, 20101, 32413, 33961, 38821, 51421, 72481, 91921, 94513, 108013, 110821, 134581, 137713, 153913, 167521, 211801, 223681, 265621, 274441, 335281, 345181, 365413, 370561, 440761, 560641

OFFSET

1,1

LINKS

Vincenzo Librandi, <a href="/A243889/b243889.txt">Table of n, a(n) for n = 1..1000</a>

MATHEMATICA

Select[Table[2 n^2 + 30 n + 13, {n, 1000}], PrimeQ]

PROG

(MAGMA) [a: n in [1..800] | IsPrime(a) where a is 2*n^2+30*n+13];

CROSSREFS

Cf. similar sequences listed in A243888.

KEYWORD

allocated

nonn,easy

AUTHOR

Vincenzo Librandi, Jun 16 2014

STATUS

approved

editing