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A251632 Circular disk sequence for the lattice of the Archimedean tiling (4,8,8). 3
1, 4, 5, 9, 15, 17, 19, 23, 28, 32, 33, 39, 41, 45, 47, 51, 53, 55, 59, 67, 71, 75, 78, 80, 82, 83, 85, 89, 93, 95, 99, 103, 107, 115, 117, 119, 121, 129, 133, 135, 137, 141, 143, 147, 149, 150, 154, 158, 160, 161, 169, 173, 177, 179, 183, 185, 187, 191, 193, 195, 199, 203, 205, 207, 211, 213 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
For the squares of the radii of the lattice point hitting circles of the Archimedean tiling (4,8,8) see A251629 and A251631.
The first differences for this sequence are given in A251633.
See the link for more details.
LINKS
FORMULA
a(n) is the number of lattice points of the Archimedean tiling (4,8,8) on the boundary and the interior of the circular disk belonging to the radius R(n) = sqrt(A251629(n) + A251631(n)*sqrt(2)), for n >= 0.
EXAMPLE
n=4: The radius of the disk is R(4) = sqrt(3 + 2*sqrt(2)), approximately 2.4142. The lattice points for this R(4)-disk are the origin, three points on the circle with radius R(1) = 1, one point on the circle with radius R(2) = sqrt(2), four points on the circle with radius R(3) = sqrt(2 + sqrt(2)) and 6 points on the circle with radius R(4) = sqrt(3 + 2*sqrt(2)), all together 1 + 3 + 1 + 4 + 6 = 15 = a(4) lattice points.
CROSSREFS
Sequence in context: A041823 A042489 A217685 * A350695 A049860 A010382
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Jan 02 2015
STATUS
approved

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Last modified April 25 04:42 EDT 2024. Contains 371964 sequences. (Running on oeis4.)