Søren Eilers has authored 89 sequences. Here are the ten most recent ones:
A319156
Number of ways to build a contiguous building with n LEGO blocks of size 1 X 2 which is flat, i.e., with all blocks in parallel position.
Original entry on oeis.org
1, 3, 11, 44, 186, 814, 3656, 16731, 77705, 365095, 1731797, 8279363, 39845689, 192852359, 937986507, 4581678031, 22464030959, 110509938701, 545269104263, 2697646445713, 13378627003520, 66495716465315, 331167284581601, 1652340114446553, 8258197397705302
Offset: 1
Cf.
A123764, but here no identification up to rotation is performed.
A317629
The number of contiguous buildings which can be built from n 1 X 2 LEGO jumper plates.
Original entry on oeis.org
1, 6, 37, 234, 1489, 9534, 61169, 393314, 2531777, 16316262, 105237737, 679336650, 4388301841, 28366361206
Offset: 1
The six different ways of connecting one such plate to another yield 6^(n-1) buildings which are of maximal height. The smallest building not of this type occurs at n=3 and has two parallel plates at the bottom level connected by one in the top level which is perpendicular to them.
- David M. McClendon and Jonathon Wilson: The entropy of LEGO jumper plates, to appear in The mathematics of various entertaining subjects. Vol. 3, Princeton University Press.
A123819
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 2 X 2 which is symmetric after a rotation by 180 degrees.
Original entry on oeis.org
1, 1, 5, 8, 65, 126, 1023, 2187, 17585, 39606, 315326, 737302
Offset: 1
A123820
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 2 X 2 which is symmetric after a rotation by 90 degrees.
Original entry on oeis.org
1, 1, 1, 1, 3, 4, 5, 10, 26, 38, 51, 121, 324, 488, 673, 1808
Offset: 1
A123821
Number of ways to build a contiguous building with n LEGO blocks of size 2 X 2 on top of a fixed block of the same size.
Original entry on oeis.org
9, 97, 1349, 20288, 329707, 5574248, 97506021, 1747201171, 31923371982, 592403479154
Offset: 1
A123822
Number of ways to build a contiguous building with n LEGO blocks of size 2 X 2 on top of a fixed block of the same size so that the building is symmetric after a rotation by 180 degrees.
Original entry on oeis.org
1, 5, 9, 44, 111, 576, 1541, 8199, 23750, 127654, 384817, 2083235
Offset: 1
A123832
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3.
Original entry on oeis.org
1, 7, 227, 9130, 408081, 19274998, 946866202, 47865420384, 2473743947058
Offset: 1
A123833
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3 which is symmetric after a rotation by 180 degrees.
Original entry on oeis.org
1, 1, 9, 22, 317, 980, 13801, 48756, 660997, 2505447
Offset: 1
A123834
Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 3 X 3 which is symmetric after a rotation by 90 degrees.
Original entry on oeis.org
1, 1, 1, 1, 7, 10, 13, 50, 190, 292, 403, 1873, 6982
Offset: 1
A123835
Number of ways to build a contiguous building with n LEGO blocks of size 3 X 3 on top of a fixed block of the same size.
Original entry on oeis.org
25, 757, 29925, 1281402, 59340183, 2862828262, 142920335981, 7311973715989
Offset: 1
Comments