Re: HP PRIME: interlinked sequences? Message #5 Posted by Alasdair McAndrew on 23 Nov 2013, 10:39 p.m., in response to message #3 by cyrille de Brébisson
The thing is that you can't expand these definitions: you will end up with infinite recursion. On the other hand, they can be computed simply as they are, by starting with U1(1), U2(1) and U3(1), then using all of those values to compute U1(2), U2(2) and U3(2) and so on.
In a sense what we have is really an iteration of vectors:
[u1, u2, u3] > [(4  u2 + u3)/4, (2  2*u1  u3)/5, (11  u1)/3]
which would be trivial if the sequence app could manage sequences of vectors, as well as numbers.
