Number of permutations p of 1,2,...,n satisfying |p(i+1)-p(i)|<>5 and |p(j+5)-p(j)|<>1 for all i=1..n-1, j=1..n-5.
A189564
Number of permutations p of 1,2,...,n satisfying |p(i+1)-p(i)|<>5 and |p(j+5)-p(j)|<>1 for all i=1..n-1, j=1..n-5.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =120a(6) =336a(7) =1474a(8) =8340a(9) =57756a(10) =475658a(11) =4171070a(12) =41950294a(13) =472535256a(14) =5882635676a(15) =79963449714
External references
- oeis: A189564