document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=151726>Question 151726</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I solve this problem?     Can You discover the lodgical pattern for each number sequence below and therby discover the missing number(shown by dash)?<BR>\n" );
document.write( "1, 3, 6, 10, __\r<BR>\n" );
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document.write( "   If you can answer thes I will be very happy<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 #804919 by </B><A HREF=/tutors/aboutme.mpl?userid=CubeyThePenguin><B>CubeyThePenguin(3113)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=CubeyThePenguin><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=CubeyThePenguin><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=804919\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Notice the following pattern:\r<BR>\n" );
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document.write( "1 = 1<BR>\n" );
document.write( "1 + 2 = 3<BR>\n" );
document.write( "1 + 2 + 3 = 6<BR>\n" );
document.write( "1 + 2 + 3 + 4 = 10\r<BR>\n" );
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document.write( "So, the next number is 1 + 2 + 3 + 4 + 5 = 15\r<BR>\n" );
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document.write( "These numbers are known as the triangular numbers. </SPAN>\n" );
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