Number of permutations of 1..n with the sum of squared adjacent differences <= (n-1)*n*(n+1)/6.
A180072
Number of permutations of 1..n with the sum of squared adjacent differences <= (n-1)*n*(n+1)/6.
Terms
- a(0) =2a(1) =2a(2) =12a(3) =62a(4) =384a(5) =2574a(6) =20432a(7) =183790a(8) =1833102a(9) =20075568a(10) =240972780a(11) =3128714960a(12) =43794182164a(13) =656192916356
External references
- oeis: A180072