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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.

A338213 a(n) is the number of free polyominoes with sprawl n.

Original entry on oeis.org

1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 3, 2, 4, 6, 13, 15, 30, 50, 93, 158, 287, 513, 950, 1735, 3212, 5945, 11099, 20720, 38910, 73002, 137821, 259757
Offset: 0

Views

Author

Sean A. Irvine and Allan C. Wechsler, Oct 17 2020

Keywords

Comments

The sprawl of a polyomino is the number of cells in a polyomino plus the number of cells adjacent to it.

Links

Crossrefs

Cf. A000105, A338211, A338212.

Formula

Antidiagonal sums of A338211.

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

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