Update README.md

Signed-off-by: Fabiana 🚀  Campanari <113218619+FabianaCampanari@users.noreply.github.com>

Author: FabianaCampanari

README.md

@@ -271,7 +271,7 @@ Ramanujan's deep insights into infinite series and modular forms continue to inf
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  Where:  
-     - **\( E \)**: Energy of a photon.
+     - $\large \color{DeepSkyBlue} \ E \$: Energy of a photon.
      - **\( h \)**: Planck's constant (\(6.626 \times 10^{-34} \, \text{J·s}\)).
      - **\( f \)**: Frequency of the radiation.