One can cheat the Rosetta Code task for topswops by using a much faster
solution:
topswop=: |.@{.,}.
topswopz=: [: ;](] <@,"_ 1 (topswop"0 1 {:))L:0~(1+[:I.(=1+i.@#)@{:)L:0
i,.0, ([: # 0 {:: _2 {[: topswopz^:(0<#)^:a: [: (<@,:@topswop"0
1~}.) >:@i.)"0 }.i=.1+i.10
1 0
2 1
3 2
4 4
5 7
6 10
7 16
8 22
9 30
10 38
This version is like sequence OEIS A000376 instead of A000375. They
differ for the first time at N=12.
For the requirements of the task it is sufficient I think. I used this
as an alternative but deleted it once I figured out it was a different
sequence.
What do you think? Entering it anyway?
--
Met vriendelijke groet,
@@i = Arie Groeneveld
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