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 A283753 Irregular triangular array read by rows: T(n,k) = the number of non-isomorphic unlabeled weakly connected digraphs on n nodes and with k edges. 3
 1, 1, 1, 3, 4, 4, 1, 1, 8, 22, 37, 47, 38, 27, 13, 5, 1, 1, 27, 108, 326, 667, 1127, 1477, 1665, 1489, 1154, 707, 379, 154, 61, 16, 5, 1, 1, 91, 582, 2432, 7694, 19646, 42148, 77305, 122953, 170315, 206982, 220768, 207301, 171008, 124110, 78813, 43862, 21209, 8951, 3242, 1043, 288, 76, 17, 5, 1, 1, 350, 3024, 17314, 74676, 266364, 808620, 2144407 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS The range for the subindex k is from n-1 to n(n-1). Obtained from A054733 by removing leading zeros. REFERENCES E. Palmer and F. Harary, Graphical Enumeration, Academic Press, 1973. LINKS Marko R. Riedel, Number of distinct connected digraphs Marko Riedel, Maple code for sequences A052283, A283753. EXAMPLE First rows are: 1; 1,    1; 3,    4,   4,   1,    1; 8,   22,  37,  47,   38,   27,   13,    5,    1,   1; 27, 108, 326, 667, 1127, 1477, 1665, 1489, 1154, 707, 379, ... CROSSREFS Cf. A000273, A000238, A003085, A052283. Sequence in context: A057279 A054733 A204255 * A120649 A001009 A120650 Adjacent sequences:  A283750 A283751 A283752 * A283754 A283755 A283756 KEYWORD nonn,tabf AUTHOR Marko Riedel, Mar 15 2017 STATUS approved

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Last modified October 20 15:29 EDT 2019. Contains 328267 sequences. (Running on oeis4.)