# Exponential integral En(x) (chart) Calculator

## Calculates a table of the exponential integral En(x) and draws the chart.

 $E_n(x)={\large\int_{\small 1}^{\hspace{25}\small\infty}\frac{\large e^{-xt}}{\large t^n}}dt$
 n [ initial value x increment repetition ]
 $\normal Exponential\ integral\ E_n(x)\\[10](1)\ E_n(x)={\large\int_{\small 1}^{\hspace{25}\small\infty}\frac{\large e^{-xt}}{\large t^n}}dt\\(2)\ E_n(0)={\large\frac{1}{n-1}}\\[10](3)\ E_1(x)=-E_i(-x)\\$
Exponential integral En(x) (chart)
 [1-3] /3 Disp-Num5103050100200
[1]  2014/11/04 07:20   Male / 60 years old level or over / A teacher / A researcher / Very /
Purpose of use
Plot variation of radiation with height for
Comment/Request
Great calculator. It would be nice to be able to export data to Excel
[2]  2013/11/14 05:08   Male / 60 years old level or over / A teacher / A researcher / Very /
Purpose of use
To compute gamma radiation variation with altitude from natural sources of gamma-radiation in the ground
[3]  2011/05/03 22:59   - / 60 years old level / Others / Very /
Purpose of use
Data will be used in a technical paper.
Comment/Request
Very useful.

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