A286868 Array read by antidiagonals: T(m,n) = number of irredundant sets in the grid graph P_m X P_n.
2, 3, 3, 5, 11, 5, 9, 26, 26, 9, 15, 79, 113, 79, 15, 26, 224, 548, 548, 224, 26, 44, 640, 2513, 4481, 2513, 640, 44, 76, 1828, 11826, 34049, 34049, 11826, 1828, 76, 130, 5225, 55136, 265227, 425926, 265227, 55136, 5225, 130
Offset: 1
Examples
Array begins: ============================================================= m\n| 1 2 3 4 5 6 7 ---|--------------------------------------------------------- 1 | 2 3 5 9 15 26 44... 2 | 3 11 26 79 224 640 1828... 3 | 5 26 113 548 2513 11826 55136... 4 | 9 79 548 4481 34049 265227 2052725... 5 | 15 224 2513 34049 425926 5467052 69724154... 6 | 26 640 11826 265227 5467052 116003176 2441933224... 7 | 44 1828 55136 2052725 69724154 2441933224 84850904785... ...
Links
- Andrew Howroyd, Table of n, a(n) for n = 1..153
- Eric Weisstein's World of Mathematics, Grid Graph
- Eric Weisstein's World of Mathematics, Irredundant Set