Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by four: p(i)<>i and (i-p(i) mod n <= 4 or p(i)-i mod n <= 4).
A260092
Number of permutations p of [n] with no fixed points and cyclic displacement of elements restricted by four: p(i)<>i and (i-p(i) mod n <= 4 or p(i)-i mod n <= 4).
Terms
- a(0) =1a(1) =0a(2) =1a(3) =2a(4) =9a(5) =44a(6) =265a(7) =1854a(8) =14833a(9) =133496a(10) =440192a(11) =1445100a(12) =4728000a(13) =15405008a(14) =49955280a(15) =162442816a(16) =530284304a(17) =1738077424a(18) =5714461760a(19) =18795784436a(20) =61868602624a(21) =203858323008a(22) =672535917712
External references
- oeis: A260092