Number of permutations of 1..n with displacements restricted to {-7,-6,-5,-4,-3,-2,0,1}.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =12a(6) =21a(7) =37a(8) =64a(9) =111a(10) =194a(11) =339a(12) =591a(13) =1030a(14) =1796a(15) =3132a(16) =5461a(17) =9522a(18) =16604a(19) =28953a(20) =50485a(21) =88030a(22) =153498a(23) =267655a(24) =466710a(25) =813802a(26) =1419027a(27) =2474358a(28) =4314538a(29) =7523260