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A057276
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Triangle T(n,k) of number of strongly connected digraphs on n unlabeled nodes and with k arcs, k=0..n*(n-1).
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10
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1, 0, 0, 1, 0, 0, 0, 1, 2, 1, 1, 0, 0, 0, 0, 1, 4, 16, 22, 22, 11, 5, 1, 1, 0, 0, 0, 0, 0, 1, 7, 58, 240, 565, 928, 1065, 953, 640, 359, 150, 59, 16, 5, 1, 1, 0, 0, 0, 0, 0, 0, 1, 10, 165, 1281, 6063, 19591, 47049, 87690, 131927, 163632, 170720, 151238, 115122, 75357, 42745, 20891, 8877, 3224, 1039, 286, 76, 17, 5, 1, 1
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listen;
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text;
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OFFSET
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1,9
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LINKS
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EXAMPLE
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Triangle begins:
[1] 1;
[2] 0,0,1;
[3] 0,0,0,1,2,1,1;
[4] 0,0,0,0,1,4,16,22,22,11,5,1,1;
...
The number of strongly connected digraphs on 3 unlabeled nodes is 5 = 1+2+1+1.
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PROG
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(PARI) \\ See PARI link in A350489 for program code.
{ my(A=A057276rows(5)); for(n=1, #A, print(A[n])) } \\ Andrew Howroyd, Jan 13 2022
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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