cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A361361 Triangle read by rows: T(n,k) is the number of bicolored cubic graphs on 2n unlabeled vertices with k vertices of the first color, n >= 0, 0 <= k <= 2*n.

Original entry on oeis.org

1, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 5, 5, 5, 2, 2, 6, 11, 33, 48, 66, 48, 33, 11, 6, 21, 68, 257, 556, 950, 1071, 950, 556, 257, 68, 21, 94, 510, 2443, 7126, 15393, 23644, 27606, 23644, 15393, 7126, 2443, 510, 94, 540, 4712, 27682, 102122, 270957, 526783, 781292, 887305, 781292, 526783, 270957, 102122, 27682, 4712, 540
Offset: 0

Views

Author

Andrew Howroyd, Mar 10 2023

Keywords

Comments

Adjacent vertices may have the same color.

Examples

			Triangle begins:
  1
  0,   0,  0;
  1,   1,  1,    1,   1;
  2,   2,  5,    5,   5,    2,   2;
  6,  11, 33,   48,  66,   48,  33,  11,   6;
  21, 68, 257, 556, 950, 1071, 950, 556, 257, 68, 21;
  ...
		

Crossrefs

Columns k=0..2 are A005638, A361410, A361411.
Row sums are A361362.
Central coefficients are A361409.
Cf. A321304 (connected), A361404.

A361407 Number of connected cubic graphs on 2n unlabeled vertices rooted at a vertex.

Original entry on oeis.org

0, 1, 2, 10, 64, 490, 4595, 51063, 657623, 9592204, 155630924, 2771922417, 53673859357, 1121581872170, 25143397213226, 601751140758134, 15310778492310274, 412656423154230159, 11743600063060974656, 351882591907696156959
Offset: 1

Views

Author

Andrew Howroyd, Mar 11 2023

Keywords

Crossrefs

Column k=1 of A321304.

Formula

G.f.: B(x)/C(x) where B(x) is the g.f. of A361410 and C(x) is the g.f. of A005638.

A361411 Number of cubic graphs on 2n unlabeled vertices rooted at a pair of indistinguishable vertices.

Original entry on oeis.org

0, 1, 5, 33, 257, 2443, 27682, 363759, 5405697, 89134360, 1609418390, 31525697245, 665263778962, 15039817276939, 362579178545598, 9284375250749758, 251643492565059981, 7197256536139662143, 216621907269166632361, 6844093745422473471562
Offset: 1

Views

Author

Andrew Howroyd, Mar 11 2023

Keywords

Crossrefs

Column k=2 of A361361.

A361409 Number of bicolored cubic graphs on 2n unlabeled vertices with n vertices of each color.

Original entry on oeis.org

1, 0, 1, 5, 66, 1071, 27606, 887305, 34583357, 1562797351, 80177945542, 4597212665432, 291214532031215, 20193430937073303, 1521240318892230748, 123711268485285686123, 10801367759750192440520, 1007762402877770768660697, 100058924666668698411972015, 10533938778032068908299390227, 1172080056205294525370971027435
Offset: 0

Views

Author

Andrew Howroyd, Mar 11 2023

Keywords

Comments

Adjacent vertices may have the same color.

Crossrefs

Central coefficients of A361361.
Showing 1-4 of 4 results.