Exercise · ZW-EXPONENTIAL-GENERATING-FUNCTION-001 · ★☆☆ Basic

What is the exponential generating function of the constant sequence \(a_n=1\)?

Choose one option.

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  • C. \(e^x\)

Explanation

The coefficients \(1/n!\) match the series of \(e^x\). The option with \(1/(1-x)\) is the ordinary generating function of that same sequence.

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Review the concept: Exponential generating function

The exponential generating function of a sequence \(a_0, a_1, \ldots\) is the formal power series \(A(x)\) whose coefficient of \(x^n\) is \(a_n/n!\).

\[A(x)=\sum_{n\ge 0}\frac{a_n}{n!}x^n\]

More practice problems: exponential generating function

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