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 1-9 of 9 results.

A244026 Analog of A140468, but starting with 5 points, and with the constraint that new points (or lines) are formed only from the intersections of lines (or points) of the same generation.

Original entry on oeis.org

5, 10, 20, 85, 2100
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Crossrefs

Related sequences: A140468, A244020-A244026.

A243707 Bisection A140468(2n+1).

Original entry on oeis.org

4, 7, 13, 97, 719725
Offset: 0

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Author

Keywords

Crossrefs

A243708 Bisection A140468(2n).

Original entry on oeis.org

0, 6, 9, 25, 1741
Offset: 0

Views

Author

Keywords

Crossrefs

A244022 Analog of A140468, but starting with 5 points instead of 4.

Original entry on oeis.org

5, 10, 20, 100, 3515
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Crossrefs

Related sequences: A140468, A244020-A244026.

A244024 Analog of A140468, but starting with 6 points instead of 4.

Original entry on oeis.org

6, 15, 51, 870, 342051
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Crossrefs

Related sequences: A140468, A244020-A244026.

A244020 Number of new points at the n-th step of the following iteration, starting with four points in general position in the real projective plane: dualize the current pointset to a family of lines, take all intersections of those lines, repeat.

Original entry on oeis.org

4, 6, 3, 3, 6, 16, 84, 1716, 719628
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Comments

A140468 is the main sequence for this problem. We have a(n) = b(n)-b(n-2), where b(n) = A140468(n).

Crossrefs

Related sequences: A140468, A244020-A244026.

A244021 Analog of A244020, but starting with 5 points instead of 4.

Original entry on oeis.org

5, 10, 15, 90, 3495
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Crossrefs

Related sequences: A140468, A244020-A244026.

A244023 Analog of A244020, but starting with 6 points instead of 4.

Original entry on oeis.org

6, 15, 45, 855, 342000
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Crossrefs

Related sequences: A140468, A244020-A244026.

A244025 Analog of A244020, but starting with 5 points, and with the constraint that new points (or lines) are formed only from the intersections of lines (or points) of the same generation.

Original entry on oeis.org

5, 10, 15, 75, 2080
Offset: 1

Views

Author

N. J. A. Sloane, Jun 20 2014

Keywords

Crossrefs

Related sequences: A140468, A244020-A244026.
Showing 1-9 of 9 results.