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A129620
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.
3
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
OFFSET
0,8
COMMENTS
Partial sums of the rows of A139621, i.e., T(n,k) = sum(A139621(n,p),p=0..k).
LINKS
FORMULA
T(n,2) = A138107(n,2) - floor(n/2).
If k >= n+1, T(n,k) = A137975(n).
EXAMPLE
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 (...)
(...)
CROSSREFS
Sequence in context: A103528 A277239 A138352 * A074766 A138107 A089631
KEYWORD
nonn,tabl
AUTHOR
Benoit Jubin, May 06 2008
EXTENSIONS
Name edited by M. F. Hasler, Jul 31 2017
Terms a(32) and beyond from Andrew Howroyd, Oct 22 2019
STATUS
approved