cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A127868 Number of square tiles in all tilings of a 3 X n board with 1 X 1 and L-shaped tiles (where the L-shaped tiles cover 3 squares).

Table of values

n a(n)
1 3
2 30
3 171
4 1044
5 5691
6 30678
7 159891
8 821100
9 4151511
10 20764590
11 102880755
12 505866804
13 2471159019
14 12004723878
15 58037429739
16 279405305676
17 1340130574407
18 6406579480446
19 30536794325547
20 145166910196116
21 688444702671291
22 3257788855054518
23 15385512460164963

List of values

[3, 30, 171, 1044, 5691, 30678, 159891, 821100, 4151511, 20764590, 102880755, 505866804, 2471159019, 12004723878, 58037429739, 279405305676, 1340130574407, 6406579480446, 30536794325547, 145166910196116, 688444702671291, 3257788855054518, 15385512460164963]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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