The OEIS is supported by the many generous donors to the OEIS Foundation.

Number of ways to build a contiguous building with n LEGO blocks of size 2 X 4 on top of a fixed block of the same size so that the building is symmetric after a rotation by 180 degrees.

0

`%I #9 Nov 29 2017 03:39:31
`

`%S 2,24,88,1079,5563,74597,412309,5633649
`

`%N Number of ways to build a contiguous building with n LEGO blocks of size 2 X 4 on top of a fixed block of the same size so that the building is symmetric after a rotation by 180 degrees.
`

`%C The base block is not counted among the n and must be the only block in the bottom layer of the building.
`

`%Y Cf. A112389, A123762 - A123827, A123829 - A123849.
`

`%K nonn,more
`

`%O 1,1
`

`%A _SÃ¸ren Eilers_, Oct 29 2006
`