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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

Table of n, a(n) for n=1..78.

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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Last modified November 18 11:26 EST 2018. Contains 317302 sequences. (Running on oeis4.)