A367671 a(n) is the numerator of the probability that the free polyomino with binary code A246521(n+1) appears in a version of the Eden growth model on the square lattice, when n square cells have been added.
1, 1, 2, 1, 5, 2, 23, 4, 1, 253, 5, 1, 23, 713, 11, 5, 149, 157, 5, 23, 1, 3671, 286417, 16, 73, 289, 1, 2657, 103, 289, 15923, 19067, 1, 1661, 1, 10019, 16591, 1, 323, 193, 1661, 2, 169, 14603, 71, 853, 11, 23, 1037, 27151, 15923, 23, 529, 487, 14267, 1
Offset: 1
Examples
As an irregular triangle: 1; 1; 2, 1; 5, 2, 23, 4, 1; 253, 5, 1, 23, 713, 11, 5, 149, 157, 5, 23, 1; ... For n = 7, the T-tetromino has binary code A246521(n+1) = 27. It can be obtained either via the straight tromino (probability 1/3 * 1/4) or via the L-tromino (probability 2/3 * 2/7), so the probability of obtaining the T-tetromino is 1/12 + 4/21 = 23/84 and a(7) = 23.
Links
- Murray Eden, A two-dimensional growth process, in: 4th Berkeley Symposium on Mathematical Statistics and Probability (Berkeley 1960), vol. 4, pp. 223-239, University of California Press, Berkeley, 1961.
- Index entries for sequences related to polyominoes.
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