A283822 Triangle read by rows: T(n,k) (n>=1, 2<=k<=n+1) = number of graphs with n edges, no isolated nodes, and k nodes in largest connected component.

1, 1, 1, 1, 2, 2, 1, 3, 4, 3, 1, 4, 7, 8, 6, 1, 6, 15, 16, 19, 11, 1, 7, 24, 34, 44, 44, 23, 1, 9, 38, 71, 97, 122, 112, 47, 1, 11, 61, 133, 211, 295, 371, 287, 106, 1, 13, 90, 249, 457, 659, 1015, 1131, 763, 235

Offset

1,5

Links

Table of n, a(n) for n=1..55.

Peter Steinbach, Field Guide to Simple Graphs, Volume 4, Part 1 (For Volumes 1, 2, 3, 4 of this book see A000088, A008406, A000055, A000664, respectively.)

Example

Triangle begins:
1,
1,1,
1,2,2,
1,3,4,3,
1,4,7,8,6,
1,6,15,16,19,11,
1,7,24,34,44,44,23,
1,9,38,71,97,122,112,47,
1,11,61,133,211,295,371,287,106,
1,13,90,249,457,659,1015,1131,763,235,
...

Crossrefs

Row sums are A000664.

Sequence in context: A208514 A179901 A209561 * A210789 A105809 A091594

Adjacent sequences: A283819 A283820 A283821 * A283823 A283824 A283825

Keyword

nonn,tabl

Author

N. J. A. Sloane, Mar 18 2017

Status

approved