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A367126
a(n) is the degree of the polyomino with binary code A246521(n+1) in the n-omino graph defined in A098891.
6
0, 0, 1, 1, 4, 3, 4, 3, 2, 10, 9, 5, 9, 10, 9, 8, 9, 10, 9, 4, 2, 16, 28, 16, 14, 12, 12, 18, 15, 20, 21, 16, 16, 16, 15, 18, 20, 11, 14, 13, 18, 6, 12, 16, 18, 11, 9, 11, 15, 22, 20, 11, 19, 14, 16, 3, 38, 36, 35, 33, 31, 32, 38, 25, 31, 38, 17, 14, 30, 14, 26
OFFSET
1,5
COMMENTS
Number of free polyominoes that can be made from the polyomino with binary code A246521(n+1) by moving one of its cells (not counting itself).
Can be read as an irregular triangle, whose m-th row contains A000105(m) terms, m >= 1.
FORMULA
a(n) >= A367439(n).
EXAMPLE
As an irregular triangle:
0;
0;
1, 1;
4, 3, 4, 3, 2;
10, 9, 5, 9, 10, 9, 8, 9, 10, 9, 4, 2;
...
For n = 8, A246521(8+1) = 30 is the binary code of the S-tetromino. By moving one cell of the S-tetromino, we can obtain the L, O, and T tetrominoes (but not the I tetromino), so a(8) = 3.
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
STATUS
approved