document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=891699>Question 891699</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1,3,6,10.15, ... , n? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #539953 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=539953\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n+=+%28k%2A%28k%2B1%29%29%2F2 ALIGN=MIDDLE  ALT=\"n+=+%28k%2A%28k%2B1%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where k is the place of the number in the sequence.  E.g., the 5th term is n = (5*6)/2 = 15, etc... </SPAN>\n" );
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