定义:
0&n=10^n
m+1&n=m&(m&…(m&n))重复n次
X&n=n&n
X+1&n=X&(X&…)重复n次
进一步还可以有X2&n=X+n&n
X^(X^2+1)&n=X^(X^2)*n&n
…
极限是X^X^…&n=X^^X&n，增长率是e0

X^^(X+1)会卡e0
处理方式是:
((X^^X)^^X)^^…
(X^^X)^^X~e1
X^^(X+1)~ew
(X^^(X+1))^^(X+1)则是从外往里拆
=(((X^^(X+1))^^X)^^X)…~e(w2)
((X^^(X+1))^^(X+1))^^(X+1)~e(w3)
X^^(X+2)~e(w^2)
X^^(X^^X)~ee0
X^^^X~z0
X^^^(X+1)=((X^^^X)^^^X)…
(X^^^X)^^^X=(X^^^X)^^(X^^^X)^^…
(X^^^X)^^X=e(z0+1)
(X^^^X)^^(X^^X)=e(z0+e0)
(X^^^X)^^(X^^^X)=e(z0*2)
(X^^^X)^^(X^^^X)^^(X^^^X)
=ee(z0*2)
(X^^^X)^^^X=z1
X^^^(X+1)=zw
X^^^(X^^^X)=zz0
X{4}X=n0
X{X}X=phi(w,0)
X{X}X+1=((X{X}X){X}X)…
{X,X,1,2}~G0

当X的运算越来越复杂时,用新的X来表示原来的X的运算.
定义:0&₂n=X^n
例:0&₂2&3=X^2&3
1&₂X+1=X^^(X+1)
X+1&₂X={X,X,1,2}
X^^X&₂X=BHO
…X&₃X&₂X&n=f_BO(n)
X&₃X&₂X&3
=3&₃X&₂X&3
=X^^^X&₂X&3
=X^^(X^^(X^^X))&₂X&3
=X^^(X^^(X^(X^2*2+X2+3)))&₂X&3
=…
=X^^(X^^(X^(…)+…+1))&₂X&3
=X^^((X^^(X^(…)+…))^^X)^^X)^^X)&₂X&3
=…