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%I M0879 N0334 #56 Oct 18 2019 04:15:02
%S 1,2,3,8,18,44,115,294,783
%N Number of ways of folding a strip of n rectangular stamps.
%C 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
%C 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
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H J. Devisme, <a href="/A002369/a002369.pdf">Contribution à l'étude du problème des timbres-poste</a>, Sphinx, 7 (Dec. 1937), 202-203. [Annotated scanned copy. Keep this link because it shows the marginal notes.]
%H J. Devisme, <a href="/A002369/a002369.jpg">Enhanced scan of first page</a>
%H J. Devisme, <a href="/A002369/a002369_1.jpg">Enhanced scan of second page</a>
%H N. J. A. Sloane, <a href="/A002369/a002369_1.pdf">Illustration of initial terms</a>
%H <a href="/index/Fo#fold">Index entries for sequences obtained by enumerating foldings</a>
%Y Cf. A056780, A326301.
%K nonn,nice,more
%O 1,2
%A _N. J. A. Sloane_
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