Javascript, 63 * 0.5 = 31.5

F=n=>{r=[m=n];while(--n){r=r.slice(0,m-n).concat(n,r)}return r}

F(4) == [ 4, 3, 2, 1, 4, 3, 2, 4, 3, 4 ]

Nothing fancy, just concatenating arrays.

Matlab, 44 * 0.5 = 22

function r=f(n);r=[];for i=1:n;r=[i:n,r];end

f(4) == [4 3 4 2 3 4 1 2 3 4]

Javascript, 63 * 0.5 = 31.5

F=n=>{r=[m=n];while(--n){r=r.slice(0,m-n).concat(n,r)}return r}

F(4) == [ 4, 3, 2, 1, 4, 3, 2, 4, 3, 4 ]

Nothing fancy, just concatenating arrays.