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 A251628 Number of lattice points of the Archimedean tiling (3,4,6,4) on the circles R(n) = sqrt(A249870(n) + A249871(n)* sqrt(3)) around any lattice point. First differences of A251627. 4
 1, 4, 2, 2, 4, 1, 4, 7, 4, 4, 2, 4, 4, 2, 4, 2, 4, 2, 2, 4, 6, 4, 4, 2, 4, 6, 4, 4, 2, 2, 2, 4, 2, 4, 4, 4, 2, 4, 2, 4, 1, 2, 4, 4, 2, 12, 2, 4, 1, 4, 4, 4, 4, 2, 4, 2, 4, 6, 4, 4, 2, 2, 2, 4, 2, 2, 4, 4, 4, 4, 4, 4, 4, 2, 2, 2, 6, 4, 2, 4, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The squares of the increasing radii of the lattice point hitting circles for the Archimedean tiling (3,4,6,4) are given in A249870 and A249871. See the notes given in a link under A251627. LINKS FORMULA a(n) = A251627(n) - A251627(n-1), for n >= 1 and a(0) = 1. EXAMPLE n = 4: on the circle with R(4) = sqrt(2 + sqrt(3)), approximately 1.932, around any lattice point lie a(4) = 4 points, namely in Cartesian coordinates, [+/-(1 + sqrt(3)/2), 1/2] and [+/-(1/2), -(1 + sqrt(3)/2)]. CROSSREFS Cf. A249870, A249871, A251627. Sequence in context: A275745 A053879 A216671 * A170988 A141035 A100854 Adjacent sequences: A251625 A251626 A251627 * A251629 A251630 A251631 KEYWORD nonn,easy AUTHOR Wolfdieter Lang, Dec 09 2014 STATUS approved

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Last modified January 30 12:01 EST 2023. Contains 359943 sequences. (Running on oeis4.)