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A002369
Number of ways of folding a strip of n rectangular stamps.
(Formerly M0879 N0334)
2
1, 2, 3, 8, 18, 44, 115, 294, 783
OFFSET
1,2
COMMENTS
Is this an erroneous version of A056780? It is unclear why one of the 9 polyominoes counted in A056780(4) should be omitted here. Devisme writes in his article that errors are likely and he cannot guarantee the exact figures but only "the order of magnitude". - M. F. Hasler, Feb 24 2018
This is different from A056780 because the polyominoes can split off (beginning at A056780(4)) while a strip of stamps always has 2 ends. - Eric Fox, Sep 01 2019
REFERENCES
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
J. Devisme, Contribution à l'étude du problème des timbres-poste, Sphinx, 7 (Dec. 1937), 202-203. [Annotated scanned copy. Keep this link because it shows the marginal notes.]
CROSSREFS
Sequence in context: A272642 A241906 A079224 * A005957 A185171 A339524
KEYWORD
nonn,nice,more
STATUS
approved