#1534 · Algebra · Sequences & series

Sum of Natural Numbers Series Expansion

If $s_{n}$ denote the sum of the first $n$ natural numbers, prove that $(1 - x)^{- 3} = s_{1} + s_{2} x + s_{3} x^{2} + \dots + s_{n} x^{n - 1} + \dots$ .

~15 minProof · checked by AIBinomial TheoremGenerating Functions

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XIV. Binomial Theorem: Any Index, Examples XIV.c, No. 19 (part 1)

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