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 A280785 Triangle read by rows: numbers of nonintersecting circles, one marked. 0
 1, 1, 1, 2, 2, 1, 5, 5, 2, 1, 13, 13, 6, 2, 1, 35, 35, 16, 6, 2, 1, 95, 95, 46, 17, 6, 2, 1, 262, 262, 128, 49, 17, 6, 2, 1, 727, 727, 364, 139, 50, 17, 6, 2, 1, 2033, 2033, 1029, 401, 142, 50, 17, 6, 2, 1, 5714, 5714, 2930, 1147, 412, 143, 50, 17, 6, 2, 1, 16136, 16136, 8344, 3299, 1184, 415, 143, 50, 17, 6, 2, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS R. J. Mathar, Topologically Distinct Sets of Non-intersecting Circles in the Plane, arXiv:1603.00077, 2016. EXAMPLE Triangle begins: 1, 1,1, 2,2,1, 5,5,2,1, 13,13,6,2,1, 35,35,16,6,2,1, 95,95,46,17,6,2,1, 262,262,128,49,17,6,2,1, 727,727,364,139,50,17,6,2,1, ... CROSSREFS Row sums are A000107. Sequence in context: A210879 A176265 A187307 * A204851 A114292 A178518 Adjacent sequences:  A280782 A280783 A280784 * A280786 A280787 A280788 KEYWORD nonn,tabl AUTHOR N. J. A. Sloane, Jan 20 2017 STATUS approved

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