function res = prfibo(t,sp,coef,vep)

l = length(sp);
s = 0;

for k = 1:l
    sk = 0;
    for m = 1:l
        sk = sk+coef(m)*vep(k,m)*exp(-i*t*sp(m));
    end
    s = s+(abs(sk))^4;
        
end

res = s;
end

