SOLUTION: 1+5+9+ ... +49+53

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