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 A233380 X-coordinate of the bottom left corner of the n X 1 brick in the greedy tiling of the first quadrant with bricks of height 1 and width 1, 2, 3... (See Comments for precise definition). 2
 0, 1, 0, 3, 7, 3, 0, 12, 9, 7, 0, 20, 18, 17, 11, 0, 32, 31, 49, 68, 49, 31, 26, 16, 0, 88, 70, 53, 49, 40, 25, 0, 114, 97, 81, 78, 70, 56, 32, 0, 147, 131, 116, 114, 107, 94, 71, 40, 0, 188, 173, 159, 158, 152, 140, 118, 88, 49, 0, 238, 224, 211, 298, 285 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS We tile the first quadrant according to the following rules: (a) We use bricks of height 1 and width 1, 2, 3, ... (b) The bricks are laid by increasing size, without overlap. (c) The left border of any brick must lie on the Y-axis or match the right border of a smaller brick. (d) The bottom border of any brick must lie on the X-axis or touch all along the top border of smaller bricks. (e) When multiple positions are possible, we choose the leftmost one. A233381 gives the Y-coordinate. LINKS Paul Tek, Table of n, a(n) for n = 1..10000 Paul Tek, PERL program for this sequence Paul Tek, Illustration of the first 1022 bricks Paul Tek, Illustration of the first 9986 bricks EXAMPLE The following diagram depicts the first 7 bricks: +-------------+ | 7 | +-----+-------+---+ | 3 | 6 | +-+---+-------+---+-----+ |1| 2 | 4 | 5 | +-+---+-------+---------+---> X 0 1 2 3 4 5 6 7 8 9 ... Hence: a(1)=a(3)=a(7)=0 a(2)=1 a(4)=a(6)=3 a(5)=7 PROG (Perl) See Link section. CROSSREFS Cf. A233381. Sequence in context: A347772 A248214 A144713 * A320027 A134731 A133368 Adjacent sequences: A233377 A233378 A233379 * A233381 A233382 A233383 KEYWORD nonn AUTHOR Paul Tek, Dec 08 2013 STATUS approved

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Last modified May 31 12:47 EDT 2023. Contains 363066 sequences. (Running on oeis4.)