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

 

Logo

Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A111199 Numbers n such that 4n + 9 is prime. 5
1, 2, 5, 7, 8, 11, 13, 16, 20, 22, 23, 25, 26, 32, 35, 37, 41, 43, 46, 47, 55, 56, 58, 62, 65, 67, 68, 71, 76, 77, 82, 85, 86, 91, 95, 97, 98, 100, 103, 106, 110, 112, 113, 125, 128, 133, 137, 140, 142, 146, 148, 151, 152, 158, 161, 163, 166, 167, 173, 175, 181, 187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Solutions of the equation (4*n+9)'=1, where n' is the arithmetic derivative of n. - Paolo P. Lava, Jan 03 2013

LINKS

Table of n, a(n) for n=1..62.

FORMULA

a(n) = A005098(n+1)-2. - R. J. Mathar, Sep 23 2009

EXAMPLE

If n=98 then 4*n + 9 = 401 (prime).

CROSSREFS

Cf. A005098, A095278, A089986.

Cf. A153238, A144562.

Sequence in context: A039580 A189296 A051279 * A138671 A032724 A153308

Adjacent sequences:  A111196 A111197 A111198 * A111200 A111201 A111202

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi, Oct 24 2005

EXTENSIONS

More terms from R. J. Mathar, Sep 23 2009

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 December 7 23:55 EST 2016. Contains 278902 sequences.