Number	Notations and Symbols	Explanation
1	$a_t$,$a_f$	OFDM signal
2	$A_n$	Input symbol sequence in the frequency domain
3	N	Subcarriers
4	t	Continuous time index
5	T	A period of an input symbol
6	$E[·]$	The mathematical expectation of signal power
7	d	Degree value
8	k	Groups from the original data
9	$y_0$	PAPR threshold
10	y	PAPR value
11	$\delta$	Probability of decoding failure
12	c	Constant
13	m	The probability that the symbol power is less than the threshold
14	${\delta }_d$	Degree for BED distribution
15	${\mu }_d$	Degree for PRSD distribution
16	$\overline{c}$	Average degree
17	$c_d$	The probability of each degree value
18	c1, c2, r1, r2	The PSO algorithm parameters
19	$v_{IJ}$	Velocity for particles in the PSO algorithm
20	$y_{IJ}$	Location for particles in the PSO algorithm
21	$P_{IJ}$	The best location for a single particle in the PSO algorithm
22	$P_{GJ}$	The best location for the population in the PSO algorithm