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Summary
svg version of the same png Normal_approximation_to_binomial.png file. Original author: User:MarkSweep

This vector image was created with gnuplot. 
gnuplot source under GPL:
# normal (Gaussian) distribution
_ln_dnorm(x, m, s) = 0.5 * log(2*pi)  log(s)  0.5*((xm)*1.0/s)**2
dnorm(x, mean, sd) = exp(_ln_dnorm(x, mean, sd))
pnorm(x, mean, sd) = norm((xmean) * 1.0/sd)
# binomial distribution
_ln_binom(x, n, p) =\
lgamma(n+1)  lgamma(x+1)  lgamma(nx+1) + x*log(p) + (nx)*log(1p)
dbinom(x, size, prob) = (x==int(x))? exp(_ln_binom(floor(x), size, prob)) : 0
pbinom(x, size, prob) =\
(x<0)? 0 : (x Licensing

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no FrontCover Texts, and no BackCover Texts. A copy of the license is included in the section entitled GNU Free Documentation License. http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue

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