A006535 - OEIS

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A006535

Number of one-sided hexagonal polyominoes with n cells.
(Formerly M2846)

1, 1, 3, 10, 33, 147, 620, 2821, 12942, 60639, 286190, 1364621, 6545430, 31586358, 153143956, 745700845, 3644379397, 17869651166, 87877879487, 433301253231, 2141584454057, 10607707971062, 52646117638427, 261756764824964, 1303625908234997, 6502430891223011, 32480041218465452, 162454295068924189, 813541940383789255, 4078750395194965720

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

REFERENCES

J. Meeus, personal communication.

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

LINKS

John Mason, Table of n, a(n) for n = 1..36

J. Meeus & N. J. A. Sloane, Correspondence, 1974-1975

Ed Pegg, Jr., Illustrations of polyforms

Eric Weisstein's World of Mathematics, Polyhex

FORMULA