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.

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A325301 a(n) is the number of edges of the stepped pyramid with n levels described in A245092.

Original entry on oeis.org

12, 21, 36, 51, 63, 84, 96, 117, 138, 165, 177, 204, 216, 240, 273, 306, 318, 351, 363
Offset: 1

Views

Author

Omar E. Pol, Apr 16 2019

Keywords

Comments

To calculate a(n) consider that levels greater than n do not exist.

Examples

			For n = 1 the first level of the stepped pyramid (starting from the top) is a cube, and a cube has 12 edges, so a(1) = 12.

Links

Crossrefs

Cf. A325300 (number of faces), A325302 (number of vertices).
Cf. A196020, A235791, A236104, A237270, A237271, A237591, A237593, A245092, A262626, A294848, A294849, A317109, A323648.

Formula

a(n) = A325300(n) + A325302(n) - 2 (Euler's formula).

A294849 a(n) is the total number of horizontal line segments that belong to the Dyck paths in the diagram of the symmetries of sigma described in A236104 and A237593 after n-th stage, with a(0) = 0.

Original entry on oeis.org

0, 1, 2, 3, 5, 6, 9, 10, 13, 15, 18, 19, 23, 24, 27, 31, 36, 37, 42, 43, 48, 52, 55, 56, 62, 65, 68, 72, 79, 80
Offset: 0

Views

Author

Omar E. Pol, Nov 09 2017

Keywords

Comments

Since the diagram is symmetrics a(n) is also the number of vertical line segments after n-th stage. For a diagram see A293750.

Crossrefs

Cf. A000203, A196020, A235791, A236104, A237048, A237591, A237593, A245092, A293750, A294847, A294848.

Formula

a(n) = A293750(n)/2.
Showing 1-2 of 2 results.

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