Number of self-inverse permutations p on [n] where the maximal displacement of an element equals 5.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =10a(7) =48a(8) =170a(9) =515a(10) =1471a(11) =4119a(12) =11605a(13) =32568a(14) =90756a(15) =250432a(16) =684816a(17) =1858440a(18) =5016359a(19) =13484339a(20) =36124302a(21) =96487740a(22) =257021991a(23) =682958487a(24) =1810749368a(25) =4791502490a(26) =12657090174a(27) =33383355375a(28) =87928909275a(29) =231312358250