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2

def t(a):
    i,j=a
    return {(i+1,j),(i,j+1),(i*2,j),(i,j*2)}
def step1(S):
    w=set()
    for i in S:
        a=t(i)
        if not a.issubset(S):
            w.add(i)
    return w
def step2(S,W):
    l=set()
    for i in S:
        a=t(i)
        if a.issubset(W):
            l.add(i)
    return l
def step3(S,L):
    w=set()
    for i in S:
        a=t(i)
        if a & L:
            w.add(i)
    return w
aa,max=17,259
st=set((i,j) for i in range(1,max) for j in range(1,max-i))
start=set((aa,j) for j in range(1,max))
w1=step1(st)
print(sorted(w1&start)[:5])
st1=st-w1
l1=step2(st1,w1)
print(sorted(l1&start))
st2=st1-l1
w2=step3(st2,l1)
print(sorted(w2&start))
st3=st2-w2
l2=step2(st2,w2.union(w1))
print(sorted(l2&start))
st4=st3-l2
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