A002369 Number of ways of folding a strip of n rectangular stamps.

1, 2, 3, 8, 18, 44, 115, 294, 783

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• nice
• more

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.]
• J. Devisme, Enhanced scan of first page
• J. Devisme, Enhanced scan of second page
• N. J. A. Sloane, Illustration of initial terms
• Index entries for sequences obtained by enumerating foldings

Crossrefs

Cf. A056780, A326301.