std::numbers Symbol Index
From cppreference.com
                    
                                        
                    < cpp | symbol index
                    
                                                            
                    This page tries to list all the symbols that are available from the standard library (numerics library) in the namespace std::numbers. The symbols are written as follows:
-  Function names with 
(). -  Templates with 
<>. 
E  I  L  P  S
E  I  L  P  S
E
e (since C++20)
e_v<> (since C++20)
egamma (since C++20)
egamma_v<> (since C++20)
I
inv_pi (since C++20)
inv_pi_v<> (since C++20)
inv_sqrt3 (since C++20)
inv_sqrt3_v<> (since C++20)
inv_sqrtpi (since C++20)
inv_sqrtpi_v<> (since C++20)
L
ln10 (since C++20)
ln10_v<> (since C++20)
ln2 (since C++20)
ln2_v<> (since C++20)
log10e (since C++20)
log10e_v<> (since C++20)
log2e (since C++20)
log2e_v<> (since C++20)
P
phi (since C++20)
phi_v<> (since C++20)
pi (since C++20)
pi_v<> (since C++20)
S
sqrt2 (since C++20)
sqrt2_v<> (since C++20)
sqrt3 (since C++20)
sqrt3_v<> (since C++20)