document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1119057>Question 1119057</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2 , 6, -18, -54, ... What will be the next term. What will be the formula?<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 #734497 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=734497\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Although there is an apparent pattern in this sequence, it is in fact impossible to answer this question (or any like it), because any subsequent numbers will form a valid sequence.<br><BR>\n" );
document.write( "Assuming the apparent pattern continues, there are many ways you could define a formula that produces the sequence.  With the signs of the terms changing on only every OTHER term, an explicit formula would be messy.<br><BR>\n" );
document.write( "One example of a recursive formula that defines the sequence could be<BR>\n" );
document.write( ".. t(1) = 2<BR>\n" );
document.write( ".. t(n) = 3*t(n-1) if n is even<BR>\n" );
document.write( ".. t(n) = -3*t(n-1) if n is odd and greater than 1 </SPAN>\n" );
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