A318778 Number of different positions that an elementary sphinx can occupy in a sphinx of order n.
1, 28, 128, 300, 544, 860, 1248, 1708, 2240, 2844
Offset: 1
Links
- Craig Knecht, 33 positions that a flacon occupies in a S4 sphinx - animated.
- Craig Knecht, Bottom row surface tension.
- Craig Knecht, Order Two Sphinx - 28 positions.
- Craig Knecht, Order three sphinx - 128 positions.
- Craig Knecht, Various shapes positioned in a order 4 sphinx.
Formula
Conjectures from Colin Barker, Nov 13 2018: (Start)
G.f.: x*(1 + 25*x + 47*x^2 - x^3) / (1 - x)^3.
a(n) = 44 - 80*n + 36*n^2 for n>1.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>4.
(End)