Terras inverse
- To: mathgroup at smc.vnet.net
- Subject: [mg43471] Terras inverse
- From: "Gino Prosapio" <billythecazz at libero.it>
- Date: Wed, 17 Sep 2003 08:00:25 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
I'm looking for a fast algorithm of inverse Terras/Collatz function (i.e.
f(m)={(2m-1)/3 (if integer), 2m}). This program should return the list:
{1},{2},{4},{8},{5,16},{3,10,32},{6,20,21,24},{12,13,40,42,128}... etc.
That correspond to the tree
1
|
2
|
4
|
8
/ \
/ \
/ \
5 16
/ \ \
3 10 32
\ \ / \
6 20 21 64
... ................. .
Thank you.