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A129620
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Square array read by falling antidiagonals: T(n,k) is the number of connected directed multigraphs with loops with n arcs and at most k vertices.
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3
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1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 2, 5, 1, 0, 1, 2, 8, 9, 1, 0, 1, 2, 8, 24, 17, 1, 0, 1, 2, 8, 32, 74, 26, 1, 0, 1, 2, 8, 32, 140, 189, 41, 1, 0, 1, 2, 8, 32, 167, 542, 460, 57, 1, 0, 1, 2, 8, 32, 167, 837, 1964, 989, 81, 1, 0, 1, 2, 8, 32, 167, 928, 4167, 6291, 2021, 106, 1, 0
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OFFSET
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0,8
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COMMENTS
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Partial sums of the rows of A139621, i.e., T(n,k) = sum(A139621(n,p),p=0..k).
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LINKS
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FORMULA
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T(n,2) = A138107(n,2) - floor(n/2).
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EXAMPLE
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1 1 1 1 1 1 ...
0 1 2 2 2 2 ...
0 1 5 8 8 8 ...
0 1 9 24 32 32 ...
0 1 17 (...)
(...)
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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