document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1127290>Question 1127290</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What's the next number in these four sequences...\r<BR>\n" );
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document.write( "3, -6, 12, 4, 20, ?\r<BR>\n" );
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document.write( "7, 16, 8, 27, 9, ?\r<BR>\n" );
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document.write( "2, 7, 26, 101, 400, ?\r<BR>\n" );
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document.write( "7, 21, 8, 72, 9, ? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #743716 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=743716\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Note that, although tutor @mathlover found patterns that predict certain next numbers for each sequence, those answers are only POSSIBLE right answers.  For virtually any sequence, there will be many rules that generate the given sequence; and the different rules are likely to produce different answers for the next number.  So any answer anybody gives is only a guess.<br><BR>\n" );
document.write( "If you like recreational mathematics, you can take the time to see IF you can find \"A\" pattern for a sequence.  But there is no way of knowing if the pattern you find is the \"right\" one, producing the \"right\" answer.<br><BR>\n" );
document.write( "So, as far as formal mathematics goes, the answer from tutor @alan3354 is right. </SPAN>\n" );
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