How to facilitate the input of syms (automatization)

Hi there. I would liket to automatize the syms input in my code such that I wouldn't have to list each sym from x1 to x21. The thing is that I also have iterations with x1 to x100 which almost makes it unbearable having to list all these syms.

The number of syms is always connected to t_end such that x1 x2 x3 .... xt_end. In this case t_end is equal to 21. Is there a way to connect these two?

syms x2 x3 x4 x5 x6 x7 x8 x9 x10 x11 x12 x13 x14 x15 x16 x17 x18 x19 x20 x21
x = [x2;x3;x4;x5;x6;x7;x8;x9;x10;x11;x12;x13;x14;x15;x16;x17;x18;x19;x20;x21];

T1 = [];
T2 = [];

t_end = length(t) -1;

for k=2:t_end
    a = trapz(t(k:k+1),q_ext(k:k+1))/(t(k+1)-t(k));             
    b = trapz(t(k:k+1),q_losses(k:k+1))/(t(k+1)-t(k));           
    c = trapz(t(k:k+1),beta_ch(k:k+1))/(t(k+1)-t(k));                                          
    d = h_ch + (x(k-1)-c).*(t(k+1)-t(k));                       
    e = 232.87.*d.^(-0.46);
    gamma_mean = (gamma(k)+gamma(k+1))/2;
    
    eqn = (a + b + gamma_mean*6.96.*x(k-1) + (6-(31*e)/1000).*x(k-1)/60*1000 + 31.*e/1000.*c/60*1000)*0.0077 - 0.0424 - x(k-1) == 0;

    vpasolve(eqn, x(k-1));
    
    beta = double(vpasolve(eqn, x(k-1)));

Answer 1

[Walter Roberson]

syms x [1,t_end]
x = x(2:end) ;  %remove x1

[Delia Bosshart]

it works, thank you!!!