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%I #28 Sep 22 2014 19:55:40
%S 3,6,12,20,48,96,184,272,576,1280,3232,6912,13568,24576,46080,73728,
%T 132096,466944,589824,1310720,3145728,4194304,14155776,18874368,
%U 59244544,119537664,150994944,335544320,847249408,1207959552,2734686208
%N Bitmasks that can be used to generate a sequence of all positive integers up to 2^n.
%C The sequence skips around in a simple pseudo-random order hitting each number from 1 to 2^n exactly once, which makes it suitable for use in e.g. a dissolve-style pixel graphics effect.
%C JavaScript code to generate all numbers from 1 to 2^n using XOR_MASK, an element of this sequence:
%C var i = 1; do { i = (i >> 1) ^ (i & 1 ? XOR_MASK : 0); } while (i != 1);
%C First few numbers of this sequence in hexadecimal, for searchability: 0x03, 0x06, 0x0C, 0x14, 0x30, 0x60, 0xB8, 0x0110, 0x0240, ...
%D Andrew S. Glassner, Graphics Gems, Academic Press, 1990, pages 221-232.
%H Mactech.com, <a href="http://www.mactech.com/articles/mactech/Vol.06/06.12/SafeDissolve/index.html">Source code for old Macintosh project</a> (see dissMask.c)
%H Ticalc.org, <a href="http://www.ticalc.org/archives/files/fileinfo/137/13705.html">Source code for TI-89 project</a> (see file dissolve.c)
%H Ticalc.org, <a href="http://tict.ticalc.org/projects.html">TI-89 project programmer's project page</a>
%K more,nonn
%O 2,1
%A _James Nylen_, Sep 05 2014
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