Number of permutations of 1..n with displacements restricted to {-6,-5,-4,-3,-2,0,1}.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =12a(6) =21a(7) =36a(8) =62a(9) =108a(10) =188a(11) =326a(12) =565a(13) =980a(14) =1700a(15) =2949a(16) =5116a(17) =8875a(18) =15395a(19) =26705a(20) =46325a(21) =80360a(22) =139400a(23) =241816a(24) =419476a(25) =727661a(26) =1262267a(27) =2189644a(28) =3798357a(29) =6588977