Number of permutations p of [n] such that max_{j=1..n} |p(j)-j| = 3.

Terms

a(0) =0a(1) =10a(2) =47a(3) =157a(4) =503a(5) =1669a(6) =5472a(7) =17531a(8) =55135a(9) =172134a(10) =535510a(11) =1660795a(12) =5133470a(13) =15826173a(14) =48706210a(15) =149721544a(16) =459820058a(17) =1411142937a(18) =4328181110a(19) =13269541967a(20) =40669595890a(21) =124617708274a(22) =381776661185