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A209325
Number of permutations of [n] with a succession but no fixed points.
2
0, 0, 0, 2, 5, 30, 163, 1172, 9349, 84208, 842149, 9266416, 111220875, 1446134218, 20248984181, 303774206310, 4860923772369, 82643503648838, 1487703851220935, 28268359232622252, 565401755237435337, 11874072125853230504, 261241878854832755345
OFFSET
0,4
COMMENTS
A succession of a permutation p is a position i such that p(i+1)-p(i) = 1.
FORMULA
a(n) = A000166(n) - A209322(n).
EXAMPLE
For n=4 we have 2341, 3412, 3421, 4123 and 4312.
KEYWORD
nonn,more
AUTHOR
Jon Perry, Jan 19 2013
EXTENSIONS
a(11)-a(14) from Alois P. Heinz, Jan 20 2013
a(15)-a(20) from Max Alekseyev, Oct 17 2017
a(21)-a(22) from Alois P. Heinz, Jul 05 2021
STATUS
approved