This site is supported by donations to The OEIS Foundation.

 Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing. Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A068531 a(n) = (3^(2^n) - 1)/2^(n + 2). 5
 1, 5, 205, 672605, 14476720225405, 13412827423017626893194723005, 23027704253395670256876704807446325518902757016163752166205, 135750441774555403090761510536778616322479346492704236319926586357457102177506285098634540189560165548644204629442284605 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Every element of this sequence is an odd number (see link). - Graeme McRae, Jan 12 2005 LINKS CROSSREFS Cf. A090129. Sequence in context: A005333 A162087 A292330 * A144139 A020541 A006413 Adjacent sequences:  A068528 A068529 A068530 * A068532 A068533 A068534 KEYWORD easy,nonn AUTHOR Benoit Cloitre, Mar 22 2002 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 13 22:48 EST 2019. Contains 329974 sequences. (Running on oeis4.)