Appendix DSummation Formulas for Series

Series arise in estimating software product performance, for example, in queueing theory. This appendix collects some useful results.

Successive terms of the arithmetic progression differ by a constant amount, d. The sum of the first n terms is

a+(a+d)+(a+2d)+(a+3d)+…+{a+(n-1)d}

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Successive terms of the geometric progression differ by a constant factor, r. The sum of the first n terms is

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If r2 < 1, then

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