OFFSET
1,2
LINKS
D. E. Knuth, Whirlpool Permutations, May 05 2020.
EXAMPLE
Triangle begins:
1,
2, 8,
6, 84, 5904,
24, 1632, 1064304, 2456909824,
120, 51040, 402671760, 15584878111040, 2179875344187129600,
720, 2340480, 273315542400, 217353588326290944, 823110394280028294344640, ...
...
CROSSREFS
KEYWORD
AUTHOR
N. J. A. Sloane, May 06 2020
STATUS
approved