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

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A108258 Consider primes p and q such that p = 3^k + 20 and q = 3^(k+1) + 20 for some k; sequence gives values of q. 0
29, 47, 101, 263, 6581, 177167 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

It appears that these values are merely conjectures. - N. J. A. Sloane (njas(AT)research.att.com), Jun 30 2005

EXAMPLE

3^1 + 20 = 23, 3^2 + 20 = 29.

PROG

(PARI) g(m, n, b) = { for(x=0, n, y=m+b^x+b%2; z=m+b^(x+1)+b%2; if(isprime(y)&isprime(z), print1(z", ") ) ) }

CROSSREFS

Sequence in context: A119891 A106754 A063642 * A042947 A134555 A164075

Adjacent sequences:  A108255 A108256 A108257 * A108259 A108260 A108261

KEYWORD

nonn

AUTHOR

Cino Hilliard (hillcino368(AT)gmail.com), Jun 29 2005

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

Content is available under The OEIS End-User License Agreement .

Last modified February 14 23:53 EST 2012. Contains 205689 sequences.