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A126743
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Triangle read by rows: T(n,k) (n>=1) gives the number of n-indecomposable polyominoes with k cells (k >= 2n).
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5
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0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 6, 5, 1, 1, 0, 0, 0, 0, 0, 0, 0, 73, 76, 80, 25, 15, 15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1044, 1475, 2205, 2643, 983, 1050, 1208, 958, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15980, 26548, 48766, 79579, 99860, 45898, 60433, 89890, 109424, 84312, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 245955, 458397, 948201, 1857965, 3160371, 4153971, 2217787, 3402761, 5855953, 9067535, 11402651, 9170285, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3807508, 7710844, 17354771, 37983463
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,12
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COMMENTS
| A polyomino is called n-indecomposable if it cannot be partitioned (along cell boundaries) into two or more polyominoes each with at least n cells.
Row n has 4n-3 terms of which the first 2n-1 are zero.
For full lists of drawings of these polyominoes for n <= 6, see the links in A125759.
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REFERENCES
| N. MacKinnon, Some thoughts on polyomino tilings, Math. Gaz., 74 (1990), 31-33.
S. Rinaldi and D. G. Rogers, Indecomposability: polyominoes and polyomino tilings, Math. Gaz., to appear, 2008.
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EXAMPLE
| Triangle begins:
0
0,0,0,1,1
0,0,0,0,0,6,5,1,1
0,0,0,0,0,0,0,73,76,80,25,15,15
0,0,0,0,0,0,0,0,0,1044,1475,2205,2643,983,1050,1208,958
0,0,0,0,0,0,0,0,0,0,0,15980,26548,48766,79579,99860,45898,60433,89890,109424,84312
0,0,0,0,0,0,0,0,0,0,0,0,0,245955,458397,948201,1857965,3160371,4153971,2217787,3402761,5855953,9067535,11402651,9170285
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3807508,7710844,17354771,37983463,...
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CROSSREFS
| Row sums give A126742. Cf. A000105, A125759, A125761, A125709, A125753.
Sequence in context: A096434 A193355 A199724 * A046613 A195774 A177824
Adjacent sequences: A126740 A126741 A126742 * A126744 A126745 A126746
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KEYWORD
| nonn,tabf
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AUTHOR
| David Applegate (david(AT)research.att.com) and N. J. A. Sloane (njas(AT)research.att.com), Feb 04 2007
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EXTENSIONS
| Rows 5, 6, 7 and 8 from David Applegate (david(AT)research.att.com), Feb 16 2007
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