Number of permutations of length 2n satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..2n, with k=3, r=3, I={-2,0,1,2}. There is no one such permutation of length 2n+1.
A079980
Number of permutations of length 2n satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..2n, with k=3, r=3, I={-2,0,1,2}. There is no one such permutation of length 2n+1.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =2a(4) =3a(5) =8a(6) =12a(7) =27a(8) =52a(9) =95a(10) =196a(11) =369a(12) =720a(13) =1408a(14) =2709a(15) =5292a(16) =10249a(17) =19894a(18) =38675a(19) =74992a(20) =145692a(21) =282823a(22) =549000a(23) =1066095a(24) =2069496a(25) =4018065a(26) =7801024a(27) =15144960a(28) =29404281a(29) =57086680
External references
- oeis: A079980