1
def b_div_by_3(n):
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    if n%3==2:
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        return (n//3)+1
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    else:
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        return n//3
6

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def b_mod_3(n):
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    if n%3==2:
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        return -1
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    else:
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        return n%3
12

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def tern(n):
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    if n==0:
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        return [0]
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    elif abs(n)==1:
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        return [n]
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    else:
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        return [b_mod_3(n)]+tern(b_div_by_3(n))
20

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def tern_powers(n):
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    t=tern(n)
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    l=len(t)
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    return [[3^(k) for k in range(len(t))],t]
25

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from sage.plot.polygon import Polygon
27

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def visual_tern(n):
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    dat=tern_powers(n)
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    exp=1/2
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    w=2*abs(n)^exp
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    pic=Graphics()
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    nb=0
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    pb=0
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    nbase=[]
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    pbase=[]
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    for k in reversed(range(len(dat[0]))):
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        if dat[1][k]>0:
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            pbase=pbase+[dat[0][k]]
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            s=dat[0][k]^exp.n()
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            pic+=polygon([(w-s,pb),(w+s,pb),(w+s,pb+s),(w-s,pb+s)])
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            pic+=text(str(dat[0][k]),(w,pb+s/2),color='yellow')
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            pb+=s
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        elif dat[1][k]<0:
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            nbase=nbase+[dat[0][k]]
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            s=dat[0][k]^exp.n()
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            pic+=polygon([(-w+s,nb),(-w-s,nb),(-w-s,nb+s),(-w+s,nb+s)])
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            pic+=text(str(dat[0][k]),(-w,nb+s/2),color='yellow')
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            nb+=s
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    if n>0:
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        s=n^exp
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        pic+=polygon([(-w+s,nb),(-w-s,nb),(-w-s,nb+s),(-w+s,nb+s)],color='black')
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        pic+=text(str(n),(-w,nb+s/2),color='red')
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    else:
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        s=(-n)^exp
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        pic+=polygon([(w+s,pb),(w-s,pb),(w-s,pb+s),(w+s,pb+s)],color='black')
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        pic+=text(str(n),(w,pb+s/2),color='red')
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    pic+=line([(-2*w,0),(2*w,0)],color='black')
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    pic+=polygon([(0,0),(w/4,-w/4),(-w/4,-w/4)],color='red')
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    pic+=text(str(n)+" = sum("+str(pbase)+")-sum("+str(nbase)+")",(0,-(abs(n)^exp)))
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    pic.show(axes=False)
62