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.

A250114 Number of orbits of size n in vertex graph of Lucas cube Lambda_n.

Original entry on oeis.org

1, 1, 1, 1, 2, 2, 4, 5, 6, 9, 12, 15, 20, 28, 30, 47, 54, 79, 88, 131, 138, 222, 232, 356, 374, 598, 602, 967, 986, 1581, 1596, 2573, 2570, 4203, 4174, 6779, 6764, 11058, 10924, 17872, 17710, 28995, 28656, 46920, 46328, 76068, 75024, 122946, 121388, 199199
Offset: 1

Views

Author

N. J. A. Sloane, Nov 19 2014

Keywords

Crossrefs

Extensions

More terms from Lars Blomberg, Dec 05 2016

A250115 Number of orbits of size 2n in vertex graph of Lucas cube Lambda_n.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 3, 5, 10, 15, 30, 44, 78, 119, 202, 310, 513, 786, 1277, 1977, 3168, 4916, 7831, 12199, 19332, 30208, 47756, 74808, 118124, 185415, 292673, 460270, 726598, 1144499, 1807638, 2851356, 4506370, 7117298, 11256870, 17799183, 28173716
Offset: 1

Views

Author

N. J. A. Sloane, Nov 19 2014

Keywords

Crossrefs

Extensions

More terms from Lars Blomberg, Dec 05 2016

A143654 Array T(n,k) read by rows: number of binary bracelets with n beads, k of them 0, with 00 prohibited, (n >= 2, 0 <= k <= floor(n/2)).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 3, 2, 1, 1, 1, 3, 3, 1, 1, 1, 4, 4, 3, 1, 1, 1, 4, 5, 4, 1, 1, 1, 5, 7, 8, 3, 1, 1, 1, 5, 8, 10, 5, 1, 1, 1, 6, 10, 16, 10, 4, 1, 1, 1, 6, 12, 20, 16, 7, 1, 1, 1, 7, 14, 29, 26, 16, 4, 1, 1, 1, 7, 16, 35, 38, 26, 8, 1, 1, 1, 8, 19, 47, 57, 50
Offset: 2

Views

Author

Washington Bomfim, Aug 28 2008

Keywords

Comments

The initial columns give A057427, A057427, A004526, A069905, A005232, A032279, A005513, A032280, A005514, A032281, A005515, A032282, A005516. Row sums give A129526.
A binary bracelet with n beads, k of them 0, with 00 prohibited has from 0 to floor(n/2) beads 0, i.e., 0 <= k <= floor(n/2). If n is even, the bracelet 0101...01 with n/2 beads of each kind does not have 00 and we cannot change any 1 of it to a 0. If n is odd we cannot change a 1 to a 0 in the bracelet 0101...011 with (n-1)/2 beads 0.
The number of binary bracelets with n beads, 0 <= k <= floor(n/2) of them 0 with 00 prohibited, is equal to the number of binary bracelets with n-k beads, k of them 0. See below.
Let B be a binary bracelet with n-k beads, k of them 0. If we insert one 1 (circularly) after a 0 of B, we obtain a bracelet with n-k+1 beads, k of them 0.
If we do this insertion k times, each time after a distinct 0 of B, we obtain a bracelet with n = n-k+k beads, k of them 0, with 00 prohibited.
On the contrary, Let B be a binary bracelet with n beads, k of them 0, with 00 prohibited. If we remove from B one 1 that is after a 0, we obtain a bracelet of n-1 beads, k of them 0. (If not and we undo the removal, the configuration obtained cannot be a bracelet and this is absurd.) If we repeat this removal k times, after each distinct bead 0, we obtain a bracelet with n-k beads, k of them 0.

Examples

			Array begins
1 1
1 1
1 1 1
1 1 1
1 1 2 1
1 1 2 1
1 1 3 2 1
1 1 3 3 1
1 1 4 4 3 1
...
A129526(10) = A057427(10) + A057427(9) + A004526(8) + A069905(7) + A005232(6) +
A032279(5) = 1+1+4+4+3+1 = 14.
		

Crossrefs

A246998 Multiplicity of the zero at x=1 of the characteristic polynomial P_n^{C0+}.

Original entry on oeis.org

1, 2, 2, 3, 3, 5, 5, 8, 9, 14, 16, 26, 31, 49, 64, 99, 133, 209, 291, 455, 657, 1022, 1510, 2359, 3545, 5536, 8442, 13201, 20319, 31836, 49353, 77436, 120711, 189674, 296854, 467160, 733363, 1155647, 1818594, 2869378, 4524081, 7146483
Offset: 1

Views

Author

N. J. A. Sloane, Sep 18 2014

Keywords

Comments

Appears to duplicate A129526. - R. J. Mathar, Sep 22 2014

Extensions

The initial terms look wrong to me. I have written to the authors.
Showing 1-4 of 4 results.