The number of permutations of {1,1,1,1,2,2,2,2,...,n,n,n,n} such that each quadruple of k's (k=1..n) is equally spaced with b(k) other elements in between, and b(1) >= b(2) >= ... >= b(n).
A332752
The number of permutations of {1,1,1,1,2,2,2,2,...,n,n,n,n} such that each quadruple of k's (k=1..n) is equally spaced with b(k) other elements in between, and b(1) >= b(2) >= ... >= b(n).
Terms
- a(0) =1a(1) =1a(2) =4a(3) =16a(4) =110a(5) =544a(6) =5444a(7) =32520a(8) =385776a(9) =3282108a(10) =40916528a(11) =354328560a(12) =7200045216a(13) =67347823160
External references
- oeis: A332752