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A062155
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Number of n-row matrices over {0,1,2} with all row and column sums equal to 1 or 2.
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2
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1, 3, 38, 1107, 58938, 5002470, 620355870, 105848185590, 23785613520480, 6809213491925040, 2419333087316808600, 1044664066287091958400, 538796052743780959419600, 327150260492074733413299600
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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REFERENCES
| I. P. Goulden and D. M. Jackson, Combinatorial Enumeration, Wiley, N.Y., 1983,(Problem 3.4.15).
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EXAMPLE
| There are 38 2-row matrices over {0,1,2} with all row and column sums equal to 1 or 2: 1 of type 2 X 1, 13 of type 2 X 2, 18 of type 2 X 3 and 6 of type 2 X 4, cf. A062154.
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CROSSREFS
| Row sums of A062154, A062156.
Sequence in context: A072331 A109518 A158119 * A099022 A136638 A163789
Adjacent sequences: A062152 A062153 A062154 * A062156 A062157 A062158
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KEYWORD
| easy,nonn
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AUTHOR
| Vladeta Jovovic (vladeta(AT)eunet.rs), Jun 06 2001
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