Number of permutations p of [n] such that |p(i) - p(i-1)| <= 2 and |p(i) - p(i-2)| <= 3.

Terms

a(0) =1a(1) =1a(2) =2a(3) =6a(4) =12a(5) =14a(6) =18a(7) =28a(8) =42a(9) =56a(10) =74a(11) =102a(12) =144a(13) =200a(14) =274a(15) =376a(16) =520a(17) =720a(18) =994a(19) =1370a(20) =1890a(21) =2610a(22) =3604a(23) =4974a(24) =6864a(25) =9474a(26) =13078a(27) =18052a(28) =24916a(29) =34390