document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=498943>Question 498943</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello:\r<BR>\n" );
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document.write( "I am working on a practice test and it would be dishonest of me to ask you the same question. However, I am having a horrible time discerning how to write a recursive pattern. I know how to find the pattern, no problem, see that right away, but when it comes to figuring out the pattern I get a mental block. \r<BR>\n" );
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document.write( "Is there a resource you can recommend to me to sort this out? I would be happy to study it as I want to understand this.\r<BR>\n" );
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document.write( "Tina \r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #337253 by </B><A HREF=/tutors/aboutme.mpl?userid=chessace><B>chessace(471)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=chessace><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=chessace><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=337253\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are several books, no doubt some of them online.<BR>\n" );
document.write( "It's easy enough to explain:<BR>\n" );
document.write( "Once you see the pattern, say it's<BR>\n" );
document.write( "1 3 7 15 31 ...<BR>\n" );
document.write( "which you see is \"double previous then add 1\",<BR>\n" );
document.write( "The recusive formula is not far off:<BR>\n" );
document.write( "x(1)=1<BR>\n" );
document.write( "for n>1, x(n)=2*x(n-1)+1<BR>\n" );
document.write( "Even sequences that are \"too easy\" such as the even numbers,<BR>\n" );
document.write( "can be expressed recursively:<BR>\n" );
document.write( "x(1)=2<BR>\n" );
document.write( "n>1: x(n)=x(n-1)+2<BR>\n" );
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