1,2

The layer sequence is the sequence of the cardinalities of the layers accumulating around a (finite-sided) polygon of the tessellation under successive side-reflections; see the illustration accompanying A054888.

G.f.: (x^4+2*x^3+4*x^2+2*x+1)/(x^4-3*x^3-x^2-3*x+1).

Sequence in context: A000343 A005324 A154638 this_sequence A056384 A036683 A054444

Adjacent sequences: A054886 A054887 A054888 this_sequence A054890 A054891 A054892

nonn

Paolo Dominici (pl.dm(AT)libero.it), May 23 2000