Number of permutations of 1..n with the sum of squared adjacent differences < n*(n-1)/2.
A180069
Number of permutations of 1..n with the sum of squared adjacent differences < n*(n-1)/2.
Terms
- a(0) =0a(1) =2a(2) =2a(3) =6a(4) =34a(5) =132a(6) =448a(7) =1986a(8) =8422a(9) =39902a(10) =195946a(11) =1024366a(12) =5505428a(13) =31185644a(14) =183904498a(15) =1119250852a(16) =7025176096a(17) =45663175776a(18) =306194071810
External references
- oeis: A180069