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

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =8a(5) =35a(6) =144a(7) =425a(8) =1035a(9) =2436a(10) =6140a(11) =16922a(12) =49176a(13) =144117a(14) =410571a(15) =1135249a(16) =3089181a(17) =8424096a(18) =23191590a(19) =64417192a(20) =179639575a(21) =500440977a(22) =1389439997a(23) =3846685210a(24) =10639680698a(25) =29446636078a(26) =81589820105a(27) =226250592841