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A137333 Spiral tiling numbers. +0
1
3, 4, 6, 12, 36, 42, 48, 192, 294, 324, 768, 2058, 2916, 3072, 12288, 14406, 26244, 49152 (list; graph; listen)
OFFSET

1,1

COMMENT

This is basically three intertwined sequences:

triangular: 3 x 1, 3 x 4, 3 x 16, ... 3 x 4 ^ n

square: 4 x 1, 4 x 9, 4 x 81, ... 4 x 9 ^ n

hexagonal: 6 x 1, 6 x 7, 6 x 49, ... 6 x 7 ^ n

Each number in the above sequence has a particular geometric interpretation:

3: a single triangular tile

4: a single square tile

6: a single hexagonal tile

12 = 3 x 4 = triangle (three sides) x 4 tiles = one triangle in the centre, with 3 equally-sized triangles surrounding it

36 = 4 x 9 = square (four sides) x 9 tiles = one square with 8 other similar copies surrounding it

42 = 6 x 7 = hexagon (six sides) x 7 tiles = one hexagon with 6 other copies surrounding it

Each number in the sequence has a prime factorisation which uniquely determines whether it corresponds to a triangular, square or hexagonal tiling and the tiling's size. Factorisation and rewriting into canonical form effectively becomes the inverse operation of "mixing" the three initial sequences.

LINKS

Author?, Spiral Honeycomb Mosaic of order 3

EXAMPLE

2058 = 6 x 7 ^ 3 = spiral honeycomb (hexagonal) mosaic of order 3, which is depicted in the linked image.

CROSSREFS

Cf. A003401.

Sequence in context: A095765 A095016 A160684 this_sequence A006719 A009287 A061080

Adjacent sequences: A137330 A137331 A137332 this_sequence A137334 A137335 A137336

KEYWORD

nonn,uned

AUTHOR

Declan Malone (declan.malone+sloane(AT)gmail.com), Apr 20 2008

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Last modified December 10 12:37 EST 2009. Contains 170569 sequences.


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