document.write( "Question 1084729: 1+5+9+ ... +49+53 \n" ); document.write( "
Algebra.Com's Answer #698803 by jorel1380(3719)\"\" \"About 
You can put this solution on YOUR website!
The equation for this is Σ(4n+1), or \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: Arithmetic Progression (AP) Solver
The first few terms of this AP are:
\n" ); document.write( "a=1, a+d=5, a+2d=9, a+3d=13, ...
\n" ); document.write( "or, just: 1, 5, 9, 13, ...\r
\n" ); document.write( "\n" ); document.write( "The Sum of the first n terms is given by:
\n" ); document.write( "\"+S%5Bn%5D=+%28n%2F2%29%282a%2B%28n-1%29d%29+\"
\n" ); document.write( "So substituting a=1, d=4 and n=14 gives:
\n" ); document.write( "\"+S%5B14%5D=+%2814%2F2%29%282%281%29%2B%2814-1%294%29+=+378+\"\r
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\n" ); document.write( " ☺☺☺☺ \n" ); document.write( "
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