login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A034936 Numbers n such that 3*n + 4 is prime. 14
1, 3, 5, 9, 11, 13, 19, 21, 23, 25, 31, 33, 35, 41, 45, 49, 51, 53, 59, 63, 65, 69, 73, 75, 79, 89, 91, 93, 101, 103, 109, 111, 115, 121, 123, 125, 131, 135, 139, 143, 145, 151, 153, 161, 165, 173, 179, 181, 189, 191, 199, 201, 203, 205, 209, 213, 219, 223, 229 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Related to hyperperfect numbers of a certain form.

LINKS

Table of n, a(n) for n=1..59.

J. S. McCranie, A study of hyperperfect numbers, J. Int. Seqs. Vol. 3 (2000) #P00.1.3.

FORMULA

a(n) = A024892(n) - 1 = 2*A024899(n) - 1.

MATHEMATICA

lst={}; Do[p=n+(n+1)+(n+3); If[PrimeQ[p], AppendTo[lst, n]], {n, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, May 22 2009 *)

Select[Range[300], PrimeQ[3#+4]&] (* Harvey P. Dale, Aug 25 2016 *)

PROG

(MAGMA) [n: n in [1..1000] |IsPrime(3*n+4)] // Vincenzo Librandi, Nov 17 2010

(PARI) is(n)=isprime(3*n+4) \\ Charles R Greathouse IV, Jul 02 2013

CROSSREFS

Cf. A038536 and A002476.

A002476 gives primes, A091178 gives prime index.

Sequence in context: A190523 A161781 A007950 * A204657 A167791 A139099

Adjacent sequences:  A034933 A034934 A034935 * A034937 A034938 A034939

KEYWORD

nonn,easy

AUTHOR

Jud McCranie

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 22 23:18 EDT 2018. Contains 316518 sequences. (Running on oeis4.)