program proviamo
    implicit none
    real:: a, b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,ab,cd,ef,gh,ij,kl,mn,op,qr,st
        a = 1.30748
        b = log10(20.45)
        c = 1.31779
        d = log10(20.69)
        e = 1.32762
        f = log10(21.20)
        g = 1.33701
        h = log10(21.74)
        i = 1.34600
        j = log10(22.13)
        k = 1.35469
        l = log10(22.60)
        m = 1.36291
        n = log10(23.03)
        o = 1.37088
        p = log10(23.56)
        q = 1.37857
        r = log10(23.91)
        s = 1.38599
        t = log10(24.36)
        ab = (a-b)**2
        cd = (c-d)**2
        ef = (e-f)**2
        gh = (g-h)**2
        ij = (i-j)**2
        kl = (k-l)**2
        mn = (m-n)**2
        op = (o-p)**2
        qr = (q-r)**2
        st = (s-t)**2
    print*, sqrt((ab+cd+ef+gh+ij+kl+mn+op+qr+st)/8)
end program