A373036 Triangle read by rows: T(n,k) is the number of edge subsets E of the n X k grid graph such that E contains a path between the top left node and the bottom right node, 1 <= k <= n.
1, 1, 7, 1, 40, 1135, 1, 216, 28942, 3329245, 1, 1144, 707239, 358911148, 167176484530, 1, 6016, 16963938, 37502829018, 74568672196498, 140386491543732211, 1, 31552, 403490839, 3856945416544, 32485805235240376, 256258754970108999490, 1946586793700869420041631
Offset: 1
Examples
Triangle begins: 1; 1, 7; 1, 40, 1135; 1, 216, 28942, 3329245; 1, 1144, 707239, 358911148, 167176484530; 1, 6016, 16963938, 37502829018, 74568672196498, 140386491543732211; ...
Links
- Eugene Nonko, Table of n, a(n) for n = 1..105 (rows 1..14, terms 1..55 from Pontus von Brömssen)
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