A153445 Take n points in general position in space; draw all planes through all triples of these points; sequence gives number of connected regions formed.

2, 15, 86, 634, 3956, 18549, 69065

Offset

3,1

Links

Table of n, a(n) for n=3..9.

A. Evnin, An elementary Introduction to Matroids, Mathematical Education 2 (33) (2005), 2-33

Formula

a(n)=1+(n^9-9n^8+6n^7+180n^6-663n^5+369n^4+3536n^3-8964n^2+2952n)/1296

Crossrefs

Cf. A055503

Sequence in context: A098624 A381065 A116079 * A376135 A208974 A294196

Adjacent sequences: A153442 A153443 A153444 * A153446 A153447 A153448

Keyword

nonn

Author

Alexander Evnin, Dec 26 2008

Status

approved