A372817 Table read by antidiagonals: T(m,n) = number of 1-metered (m,n)-parking functions.
1, 0, 2, 0, 3, 3, 0, 4, 8, 4, 0, 6, 21, 15, 5, 0, 8, 55, 56, 24, 6, 0, 12, 145, 209, 115, 35, 7, 0, 16, 380, 780, 551, 204, 48, 8, 0, 24, 1000, 2912, 2640, 1189, 329, 63, 9, 0, 32, 2625, 10868, 12649, 6930, 2255, 496, 80, 10, 0, 48, 6900, 40569, 60606, 40391, 15456, 3905, 711, 99, 11
Offset: 1
Examples
For T(3,2) the 1-metered (3,2)-parking functions are 111, 121, 211, 212. Table begins: 1, 2, 3, 4, 5, 6, 7, ... 0, 3, 8, 15, 24, 35, 48, ... 0, 4, 21, 56, 115, 204, 329, ... 0, 6, 55, 209, 551, 1189, 2255, ... 0, 8, 145, 780, 2640, 6930, 15456, ... 0, 12, 380, 2912, 12649, 40391, 105937, ... 0, 16, 1000, 10868, 60606, 235416, 726103, ... ...
Links
- Spencer Daugherty, Pamela E. Harris, Ian Klein, and Matt McClinton, Metered Parking Functions, arXiv:2406.12941 [math.CO], 2024.
Crossrefs
Formula
T(m,n) = (n*(n+sqrt(n^2 - 4))-2)/(n*(n+sqrt(n^2 - 4))-4)*((n+sqrt(n^2-4))/2)^m + (n*(n-sqrt(n^2 - 4))-2)/(n*(n-sqrt(n^2 - 4))-4)*((n-sqrt(n^2-4))/2)^m.
T(m,n) = n*T(m-1,n) - T(m-2,n) with T(0,n) = 1.