So this aren’t valid permutations?

karl@h3002993:~/src/perl$ ./pmute.pl
1 8 1 2 1 7 1 3 1 6 1 5 1 4 1
karl@h3002993:~/src/perl$ ./pmute.pl
1 3 1 4 1 7 1 5 1 2 1 6 1 8 1
karl@h3002993:~/src/perl$ ./pmute.pl
1 4 1 8 1 6 1 5 1 3 1 2 1 7 1
karl@h3002993:~/src/perl$ ./pmute.pl
1 5 1 8 1 2 1 4 1 6 1 3 1 7 1
karl@h3002993:~/src/perl$ ./pmute.pl
1 7 1 5 1 4 1 3 1 8 1 2 1 6 1

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FYI

karl@h3002993:~/src/perl$ time ./pmute.pl
1 4 1 3 1 2 1 6 1 5 1 7 1 8 1

real    0m0,081s
user    0m0,076s
sys     0m0,004s

karl@h3002993:~/src/perl$ lscpu
 Architecture:        x86_64
CPU op-mode(s):      32-bit, 64-bit
Address sizes:       46 bits physical, 48 bits virtual
Byte Order:          Little Endian
CPU(s):              1
On-line CPU(s) list: 0
Vendor ID:           GenuineIntel
Model name:          Intel(R) Xeon(R) CPU E5-2680 v3 @ 2.50GHz
…

[download]

«The Crux of the Biscuit is the Apostrophe»

In reply to Re^7: Algorithm RFC: fast (pseudo-)random shuffle with no repetition by karlgoethebier
in thread Algorithm RFC: fast (pseudo-)random shuffle with no repetition by Anonymous Monk

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