A263683 T(n,k)=Number of length n arrays of permutations of 0..n-1 with each element moved by -k to k places and with no two consecutive decreases.
1, 1, 2, 1, 2, 3, 1, 2, 5, 5, 1, 2, 5, 12, 8, 1, 2, 5, 17, 26, 13, 1, 2, 5, 17, 53, 58, 21, 1, 2, 5, 17, 70, 155, 131, 34, 1, 2, 5, 17, 70, 277, 429, 295, 55, 1, 2, 5, 17, 70, 349, 1009, 1210, 662, 89, 1, 2, 5, 17, 70, 349, 1658, 3487, 3457, 1487, 144, 1, 2, 5, 17, 70, 349, 2017
Offset: 1
Examples
Some solutions for n=7 k=4 ..2....2....0....0....0....4....1....1....1....3....0....2....2....1....0....2 ..0....3....4....2....1....0....5....3....2....4....5....4....1....4....4....0 ..3....0....3....1....4....1....2....6....0....5....1....0....5....6....5....1 ..4....4....6....4....3....3....3....0....4....6....2....6....0....0....1....6 ..5....1....1....5....5....6....0....2....6....0....3....1....4....2....6....3 ..1....6....2....6....6....2....4....5....3....1....4....5....6....3....2....5 ..6....5....5....3....2....5....6....4....5....2....6....3....3....5....3....4
Links
- R. H. Hardin, Table of n, a(n) for n = 1..484
Formula
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2)
k=2: a(n) = 2*a(n-1) +a(n-3) +a(n-4) -a(n-5)
k=3: [order 20]
k=4: [order 70]
Comments