1,6

Turning over the necklace is not allowed.

M. R. Nester (1999). Mathematical investigations of some plant interaction designs. PhD Thesis. University of Queensland, Brisbane, Australia.

A054625(n)-6*A001869(n)+15*A001868(n)-20*A001867(n)+15*A000031(n)-6.

Cf. A054625.

Sequence in context: A110839 A084030 A056291 this_sequence A038745 A032180 A000553

Adjacent sequences: A056283 A056284 A056285 this_sequence A056287 A056288 A056289

nonn

Marks R. Nester (nesterm(AT)dpi.qld.gov.au)