Изменения

calculate '''for''' (i = k<tex>\cdots</tex>2k - 1) { a[i] = <tex>\sum\limits_{j = 1}^{k], a}</tex> -q[k + 1j], <tex>\cdotscdot</tex>, a[2k i - 1j]; } <tex>R = Q(t) \cdot Q(-t)</tex>; leave filter a[i] with (i % mod 2 == n % mod 2);

n = n div 2;

return a[n];