document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1055640>Question 1055640</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello. \r<BR>\n" );
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document.write( "I have a sequence : 4 8 28 108 608 3108<BR>\n" );
document.write( "I can't solve it. <BR>\n" );
document.write( "How to do it?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #670828 by </B><A HREF=/tutors/aboutme.mpl?userid=addingup><B>addingup(3677)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=addingup><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=addingup><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=670828\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The beginning of your sequence follows the pattern of alternate 3^n+1 and 3^n-1. But then you go 108, 608, 3108 and that pattern, if there is one, I have not yet figured out.<BR>\n" );
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document.write( "3^1+1 = 4<BR>\n" );
document.write( "3^2-1 = 8<BR>\n" );
document.write( "3^3+1 = 28<BR>\n" );
document.write( "If you follow this pattern, the next three numbers would be: <BR>\n" );
document.write( "3^4-1 = 80<BR>\n" );
document.write( "3^5+1 = 244<BR>\n" );
document.write( "3^6-1 = 728 </SPAN>\n" );
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