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A327372 Triangle read by rows where T(n,k) is the number of unlabeled simple graphs covering n vertices with exactly k endpoints (vertices of degree 1). 5
1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 3, 1, 1, 1, 1, 11, 5, 4, 1, 2, 0, 62, 29, 18, 6, 4, 2, 1, 510, 225, 101, 32, 13, 4, 3, 0, 7459, 2674, 842, 223, 72, 19, 9, 3, 1, 197867, 50834, 10784, 2171, 504, 115, 34, 9, 4, 0, 9808968, 1653859, 228863, 32322, 5268, 944, 209, 46, 16, 4, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,11

LINKS

Table of n, a(n) for n=0..65.

Gus Wiseman, The unlabeled graphs covering 5 vertices with k endpoints.

FORMULA

Column-wise first differences of A327371.

EXAMPLE

Triangle begins:

   1

   0  0

   0  0  1

   1  0  1  0

   3  1  1  1  1

  11  5  4  1  2  0

CROSSREFS

Row sums are A002494.

Column k = 0 is A261919.

The non-covering version is A327371.

The labeled version is A327377.

Cf. A000088, A004110, A294217, A327227, A327369, A327370.

Sequence in context: A141901 A200473 A180172 * A328323 A090751 A322127

Adjacent sequences:  A327369 A327370 A327371 * A327373 A327374 A327375

KEYWORD

nonn,tabl

AUTHOR

Gus Wiseman, Sep 04 2019

EXTENSIONS

Terms a(21) and beyond from Andrew Howroyd, Sep 11 2019

STATUS

approved

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Last modified March 28 14:53 EDT 2020. Contains 333089 sequences. (Running on oeis4.)