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A005519 Let T(n,d) = number of distinct d-dimensional polyominoes (or polycubes) with n cells (A049429, A049430); sequence gives Sum_{d} T(n,d).
(Formerly M1775)
5
1, 1, 2, 7, 26, 153, 1134, 11050, 128987, 1765252, 27418060 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

These are free polyominoes, meaning that they are counted up to rotation, reflection, and translation. - Peter Kagey, Apr 30 2020

REFERENCES

Dan Hoey, Bill Gosper and Richard C. Schroeppel, Discussions in Math-Fun Mailing list, circa Jul 13 1999.

W. F. Lunnon, personal communication.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

Table of n, a(n) for n=1..11.

R. C. Schroeppel, A few mathematical experiments

CROSSREFS

Row sums of A049429 or A049430.

Sequence in context: A209005 A068870 A345682 * A290305 A343595 A329011

Adjacent sequences:  A005516 A005517 A005518 * A005520 A005521 A005522

KEYWORD

nonn,nice,hard,more

AUTHOR

N. J. A. Sloane.

EXTENSIONS

a(9) from Richard C. Schroeppel

a(10) and a(11) from Peter Kagey, Apr 30 2020, based on the rows John Niss Hansen added to A049430.

STATUS

approved

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Last modified September 22 19:36 EDT 2021. Contains 347608 sequences. (Running on oeis4.)