A123814 Number of ways to build a contiguous building with n LEGO blocks of size 1x8 on top of a fixed block of the same size.

79, 8509, 1273567, 211300931, 37827088513

Offset

1,1

Comments

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

Links

Table of n, a(n) for n=1..5.

Crossrefs

Cf. A112389, A123762 - A123827, A123829 - A123849.

Sequence in context: A038531 A032910 A116235 * A265446 A145317 A363515

Adjacent sequences: A123811 A123812 A123813 * A123815 A123816 A123817

Keyword

nonn,hard

Author

Søren Eilers, Oct 29 2006

Status

approved