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.

A344334 a(n) is the number of large or small squares that are used to tile primitive squares of type 1 whose length of side is A344333(n).

Original entry on oeis.org

20, 90, 272, 468, 650, 1332, 2900, 3600, 2450, 7650, 4160, 6642, 10388, 16400, 10100, 25578, 14762, 27540, 20880, 42048, 50960, 54900, 28730, 90650, 60500, 38612, 98100, 50850, 125712, 142400, 149940, 65792, 141570, 116948, 214650, 83810, 105300, 265232, 354368
Offset: 1

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Author

Bernard Schott, Jun 02 2021

Keywords

Comments

Some notations: s = side of the tiled squares, a = side of small squares, b = side of large squares, and z = number of small squares = number of large squares.
Every term is of the form z = (a*b)^2 * (a^2+b^2) with gcd(a, b) = 1.
Every primitive square is composed of m = a*b * (a^2+b^2) elementary rectangles of length L = a^2+b^2 and width W = a*b, so with an area A = a*b * (a^2+b^2) = m.
This sequence is not increasing: a(9) = 2450 < a(8) = 3600.
Every term is even.
If a = 1 and b = n > 1, then number of squares z = n^2 * (n^2+1) is in A071253 \ {0,2}.

Examples

			Square 10 x 10 with a = 1, b = 2, s = 10, z = 20.
      ___ ___ _ ___ ___ _
     |   |   |_|   |   |_|
     |___|___|_|___|___|_|
     |   |   |_|   |   |_| with 10 elementary 2 x 5 rectangles
     |___|___|_|___|___|_|
     |   |   |_|   |   |_|              ___ ___ _
     |___|___|_|___|___|_|             |   |   |_|
     |   |   |_|   |   |_|             |___|___|_|
     |___|___|_|___|___|_|
     |   |   |_|   |   |_|
     |___|___|_|___|___|_|
		

References

  • Ivan Yashchenko, Invitation to a Mathematical Festival, pp. 10 and 102, MSRI, Mathematical Circles Library, 2013.

Crossrefs

Cf. A071253 \ {0,2} is a subsequence.