<?xml version="1.0" encoding="utf-8"?><!DOCTYPE article  PUBLIC '-//OASIS//DTD DocBook XML V4.4//EN'  'http://www.docbook.org/xml/4.4/docbookx.dtd'><article><articleinfo><title>FAQ/combinatorics/others</title><revhistory><revision><revnumber>11</revnumber><date>2015-07-02 11:17:32</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>10</revnumber><date>2015-07-02 11:17:16</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>9</revnumber><date>2015-07-02 11:16:33</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>8</revnumber><date>2015-07-02 11:16:17</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>7</revnumber><date>2015-07-02 11:14:53</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>6</revnumber><date>2015-07-02 11:13:41</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>5</revnumber><date>2015-07-02 11:11:22</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>4</revnumber><date>2015-07-02 11:11:08</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>3</revnumber><date>2015-07-02 11:10:56</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>2</revnumber><date>2015-07-02 11:10:38</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>1</revnumber><date>2015-07-02 11:10:05</date><authorinitials>PeterWatson</authorinitials></revision></revhistory></articleinfo><section><title>One instance of 3 reps and one instance of 4 reps</title><para>An example of one instance of 3 reps is AAAABC. There are (6 choose 2) possible positions of the two non-repeated stimuli in a sequence of length 6. These are </para><screen><![CDATA[12
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