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.

A353070 Solution to Forest of Numbers (Bosque de Números) puzzle for Transparent Queens starting with numbers 1 and 2 for an n X n square grid (see Comments).

Original entry on oeis.org

3, 5, 8, 10, 13, 15, 17, 19
Offset: 2

Views

Author

Rodolfo Kurchan, Apr 21 2022

Keywords

Comments

Start with an n X n square grid. Each cell has neighbors horizontally, vertically and diagonally. Place the numbers 1 and 2 anywhere. Now place the numbers 3, 4, ..., m in order, subject to the rule that when you place k, the sum of the numbers in the same row, column and diagonal must equal k. Then a(n) is the maximum m that can be achieved.

Examples

			Solutions for 5 <= n <= 8 from _Pontus von Brömssen_:
  +---+---+---+---+---+
  | 1 |   | 2 | 8 |   |
  +---+---+---+---+---+
  | 9 | 3 | 5 |   |   |
  +---+---+---+---+---+
  |   |   |   |   | 6 |
  +---+---+---+---+---+
  |   |10 |   |   |   |
  +---+---+---+---+---+
  |   | 7 |   |   | 4 |
  +---+---+---+---+---+
.
  +---+---+---+---+---+---+
  | 1 | 9 |   | 8 |   |   |
  +---+---+---+---+---+---+
  |   |   |   | 7 |   |12 |
  +---+---+---+---+---+---+
  |10 |   |   |   |   |   |
  +---+---+---+---+---+---+
  |   |   | 6 |   |   | 2 |
  +---+---+---+---+---+---+
  | 5 |   |   |   |11 |   |
  +---+---+---+---+---+---+
  | 4 |   |13 |   |   | 3 |
  +---+---+---+---+---+---+
.
  +---+---+---+---+---+---+---+
  |   | 8 |   | 6 |   |   |   |
  +---+---+---+---+---+---+---+
  |   |11 | 2 |   |   |   |   |
  +---+---+---+---+---+---+---+
  |   |   |   |   | 5 |   |15 |
  +---+---+---+---+---+---+---+
  | 3 |   |   | 1 |   |   |10 |
  +---+---+---+---+---+---+---+
  |14 |   |   |   |   |   |   |
  +---+---+---+---+---+---+---+
  | 7 |   |12 |   |   |   |   |
  +---+---+---+---+---+---+---+
  | 4 |   |   |   | 9 |13 |   |
  +---+---+---+---+---+---+---+
.
  +---+---+---+---+---+---+---+---+
  | 1 | 3 |   |12 | 6 |   | 2 |   |
  +---+---+---+---+---+---+---+---+
  | 4 |   |   |   |   |   |11 |   |
  +---+---+---+---+---+---+---+---+
  |   |   | 7 |   |15 |   |   |   |
  +---+---+---+---+---+---+---+---+
  |   |   |   |   |   |   |   |14 |
  +---+---+---+---+---+---+---+---+
  |   |13 |   |   |   |   |   |   |
  +---+---+---+---+---+---+---+---+
  |10 |   |   |   |   |   | 5 |   |
  +---+---+---+---+---+---+---+---+
  |   |   |16 |   |   | 9 |   |   |
  +---+---+---+---+---+---+---+---+
  |   |   |   |   |   |17 |   | 8 |
  +---+---+---+---+---+---+---+---+
Solution for a(9) = 19 from Giorgio Vecchi
		

Crossrefs