A201042 T(n,k)=Number of -k..k arrays of n elements with adjacent element differences also in -k..k.
3, 5, 7, 7, 19, 17, 9, 37, 75, 41, 11, 61, 203, 295, 99, 13, 91, 429, 1111, 1161, 239, 15, 127, 781, 3011, 6083, 4569, 577, 17, 169, 1287, 6691, 21141, 33305, 17981, 1393, 19, 217, 1975, 13021, 57343, 148433, 182349, 70763, 3363, 21, 271, 2873, 23045, 131781
Offset: 1
Examples
Some solutions for n=4 k=7 .-5...-1....2....2...-3....4...-4....4....5....2...-6...-1....1....4....2....0 .-3....0....3....1....2....4...-3....4....2...-5....1....6....5....7....4....0 .-5...-5...-4...-3....2...-2....1....5....7...-7....0....2....4....1....1....2 .-7...-1....2...-6....1...-1...-5....7....0...-1...-5....6...-3....5...-1....2
Links
- R. H. Hardin, Table of n, a(n) for n = 1..9999
Crossrefs
Formula
Empirical for columns:
k=1: a(n) = 2*a(n-1) +a(n-2)
k=2: a(n) = 4*a(n-1) -a(n-3)
k=3: a(n) = 5*a(n-1) +3*a(n-2) -2*a(n-3) -a(n-4)
k=4: a(n) = 7*a(n-1) +a(n-2) -6*a(n-3) +a(n-5)
k=5: a(n) = 8*a(n-1) +6*a(n-2) -9*a(n-3) -5*a(n-4) +2*a(n-5) +a(n-6)
k=6: a(n) = 10*a(n-1) +3*a(n-2) -18*a(n-3) -a(n-4) +8*a(n-5) -a(n-7)
k=7: a(n) = 11*a(n-1) +10*a(n-2) -24*a(n-3) -15*a(n-4) +13*a(n-5) +7*a(n-6) -2*a(n-7) -a(n-8)
Empirical for rows:
n=1: a(k) = 2*k + 1
n=2: a(k) = 3*k^2 + 3*k + 1
n=3: a(k) = (14/3)*k^3 + 7*k^2 + (13/3)*k + 1
n=4: a(k) = (29/4)*k^4 + (29/2)*k^3 + (51/4)*k^2 + (11/2)*k + 1
n=5: a(k) = (169/15)*k^5 + (169/6)*k^4 + 32*k^3 + (119/6)*k^2 + (101/15)*k + 1
n=6: a(k) = (2101/120)*k^6 + (2101/40)*k^5 + (1753/24)*k^4 + (1405/24)*k^3 + (569/20)*k^2 + (119/15)*k + 1
n=7: a(k) = (17141/630)*k^7 + (17141/180)*k^6 + (28177/180)*k^5 + (2759/18)*k^4 + (17299/180)*k^3 + (6929/180)*k^2 + (1921/210)*k + 1
Comments