limite = 2000
dim stern(limite+2)

sub SternBrocot()
    stern(1) = 1
    stern(2) = 1

    i = 2 : n = 2 : ub = arraysize(stern(),1)

    while i < ub
        i = i + 1
        stern(i) = stern(n) + stern(n -1)
        i = i + 1
        stern(i) = stern(n)
        n = n + 1
    wend
end sub

sub gcd(p, q)
    if q = 0 return p
    return gcd(q, mod(p, q))
end sub

SternBrocot()

print "The first 15 are: ";
for i = 1 to 15
    print stern(i), " ";
next i

print "\n\n  Index   First nr."
d = 1
for i = 1 to limite
    if stern(i) = d then
        print i using "######", stern(i) using "######"
        d = d + 1
        if d = 11 d = 100
        if d = 101 break
        i = 0
    end if
next i

print : print
d = 0
for i = 1 to 1000
    if gcd(stern(i), stern(i+1)) <> 1 then
        d = gcd(stern(i), stern(i+1))
        break
    end if
next i

if d = 0 then
    print "GCD of two consecutive members of the series up to the 1000th member is 1"
else
    print "The GCD for index ", i, " and ", i+1, " = ", d
end if