document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=927481>Question 927481</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the number missing in the sequence below?\r<BR>\n" );
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document.write( "4,7,11,17 (), 39\r<BR>\n" );
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document.write( "is it 26?<BR>\n" );
document.write( " 4+2=6<BR>\n" );
document.write( "7+2=9<BR>\n" );
document.write( "11+2=13\r<BR>\n" );
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document.write( "then,\r<BR>\n" );
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document.write( "7+4=11<BR>\n" );
document.write( "11+6=17<BR>\n" );
document.write( "17+9=26<BR>\n" );
document.write( "26+13=39<BR>\n" );
document.write( "is this correct? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #563054 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=563054\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 26 seems like the best answer. If you look at the common differences when () = 26, you obtain 3, 4, 6, 9, 13. Looking at the common differences of the next sequence, we have 1, 2, 3, 4, and then 1, 1, 1. However one could probably provide a convincing argument of why 25 or 27 is the missing number, or any number, since sequences can be arbitrary. These types of sequence problems generally aren't very good. </SPAN>\n" );
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