A281347 Row sums of A281348.

1, 3, 8, 27, 90, 330, 1225, 4729, 18554, 74234, 300828, 1233992, 5110067, 21341337, 89768701, 379995230, 1617476520, 6918987187, 29727655820, 128233521698, 555136090343, 2411084930425, 10503086930643, 45878043207696, 200900611229570, 881783809570251

Offset

1,2

Links

Table of n, a(n) for n=1..26.

R. J. Mathar, Topologically Distinct Sets of Non-intersecting Circles in the Plane, arXiv:1603.00077 [math.CO], 2016.

Crossrefs

Cf. A281348.

Sequence in context: A148840 A374570 A047153 * A000238 A259811 A148841

Adjacent sequences: A281344 A281345 A281346 * A281348 A281349 A281350

Keyword

nonn

Author

N. J. A. Sloane, Jan 20 2017

Status

approved