is mentioned by

Def f91(i) == if 100 < i i-10 else f91(f91(i+11)) fi (recursive)	[f91]
Def process u j where process s i == if P(i;s) then F(i;s) else G(i;s) where xs := N(i;s); s:= H(i;s); while not null xs { s := process s (hd xs); xs := tl xs; } == if P(j;u) F(j;u) else G(j;list_accum(s',i'.process s' i' where process s i == if P(i;s) then F(i;s) else G(i;s) where xs := N(i;s); s:= H(i;s); while not null xs { s := process s (hd xs); xs := tl xs; } ;H(j;u);N(j;u))) fi (recursive)	[accumulate]
Def upto(i;j) == if i < j [i / upto(i+1;j)] else nil fi (recursive)	[upto]

In prior sections: list 1 prog 1 mb basic mb nat mb list 1 num thy 1

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