Number of planar n X n X n binary triangular grids with mirror symmetry about one altitude with every one adjacent to exactly 2 other ones.

A153987

Number of planar n X n X n binary triangular grids with mirror symmetry about one altitude with every one adjacent to exactly 2 other ones.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =12a(6) =33a(7) =97a(8) =381a(9) =1490a(10) =7757a(11) =42774a(12) =307960a(13) =2294754a(14) =22718581a(15) =231171797a(16) =3121763126a(17) =43651298703a(18) =807916379400

External references