=+2.23. 1 Extend (2.29) to ordinals & < 2 as follows. Replace the right side of (2.28)

by Un- ((A2, -, VAS ,, ). Suppose that $g is defined for B <

a. Let B .(1), B.(2) ,... be a sequence of ordinals such that B (n) <« and such that if B <

a, then B = B (n) for infinitely many even n and for infinitely many odd n;