

A292881


Number of nstep closed paths on the E6 lattice.


2




OFFSET

0,3


COMMENTS

Calculated by brute force computational enumeration.
The moments of the imaginary part of the suitably normalized E6 lattice Green's function.


LINKS

Table of n, a(n) for n=0..9.
S. Savitz and M. Bintz, Exceptional Lattice Green's Functions, arXiv:1710.10260 [mathph], 2017.


FORMULA

Summed combinatorial expressions and recurrence relations for this sequence exist, but have not been determined. These would allow one to write a differential equation or hypergeometric expression for the E6 lattice Green's function.


EXAMPLE

The 2step walks consist of hopping to one of the 72 minimal vectors of the E6 lattice and then back to the origin.


CROSSREFS

Cf. A126869 (Linear A1 lattice), A002898 (Hexagonal A2), A002899 (FCC A3), A271432 (D4), A271650 (D5), A271651 (D6), A292882 (E7), A271670 (D7), A292883 (E8), A271671 (D8).
Sequence in context: A239423 A128800 A008391 * A282018 A037251 A234209
Adjacent sequences: A292878 A292879 A292880 * A292882 A292883 A292884


KEYWORD

nonn,walk,more


AUTHOR

Samuel Savitz, Sep 26 2017


STATUS

approved



