Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=1, r=5, I={4}.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =8a(5) =15a(6) =30a(7) =58a(8) =113a(9) =220a(10) =429a(11) =835a(12) =1627a(13) =3169a(14) =6173a(15) =12024a(16) =23422a(17) =45623a(18) =88869a(19) =173107a(20) =337194a(21) =656817a(22) =1279409a(23) =2492150a(24) =4854439a(25) =9455922a(26) =18419114a(27) =35878442a(28) =69887326a(29) =136132954