Prime & HP 38G: Comparison of Sequence App

[Gerald H]

This thread was prompted by one in the General Forum

http://www.hpmuseum.org/forum/thread-3258.html

from which I quote:

For

http://oeis.org/search?q=a004001&languag...&go=Search

This works on the 38G:

U1(1)=1
U1(2)=1
U1(N)=U1(U1(N-1))+U1(N-U1(N-1)).

On the Prime it refuses to get ticked.

Why?

End of quote.

While the Prime has added colour & easy legibility of the screen it's actual utiliy for easily producing various series, in particular the one above, is smaller than the 38G's.

I would be pleased if someone could diasabuse me of this opinion by demonstrating how to reproduce the series in question, & preferably with equivalent simplicity.