document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1182229>Question 1182229</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the nth term for the following sequence:\r<BR>\n" );
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document.write( "10, 30, 60, 100, 150, 210, ... </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #812194 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=812194\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "If each term is divided by 10, the sequence is<br><BR>\n" );
document.write( "1, 3, 6, 10, 15, 21, ...<br><BR>\n" );
document.write( "You might recognize that sequence as the triangular numbers; or as the sequence in which the n-th term is the sum of the integers 1 through n.<br><BR>\n" );
document.write( "The formula for the n-th triangular number is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28n%29%28n%2B1%29%29%2F2 ALIGN=MIDDLE  ALT=\"%28%28n%29%28n%2B1%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "So the n-th term of this sequence is<br><BR>\n" );
document.write( "ANSWER: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=10%28%28%28n%29%28n%2B1%29%29%2F2%29 ALIGN=MIDDLE  ALT=\"10%28%28%28n%29%28n%2B1%29%29%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( " </SPAN>\n" );
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