%I A000136 M1614 N0630
%S A000136 1,2,6,16,50,144,462,1392,4536,14060,46310,146376,485914,1557892,5202690,
               16861984,
%T A000136 56579196,184940388,622945970,2050228360,6927964218,22930109884,77692142980,
%U A000136 258360586368,877395996200,2929432171328,9968202968958,33396290888520,
               113837957337750
%N A000136 Number of ways of folding a strip of n labeled stamps.
%D A000136 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A000136 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A000136 J. E. Koehler, Folding a strip of stamps, J. Combin. Theory, 5 (1968), 
               135-152.
%D A000136 W. F. Lunnon, A map-folding problem, Math. Comp. 22 (1968), 193-199.
%D A000136 M. B. Wells, Elements of Combinatorial Computing. Pergamon, Oxford, 1971, 
               p. 238.
%H A000136 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               StampFolding.html">Link to a section of The World of Mathematics.</
               a>
%H A000136 <a href="Sindx_Fo.html#fold">Index entries for sequences obtained by 
               enumerating foldings</a>
%Y A000136 Equals 2n*A000560.
%Y A000136 Sequence in context: A052890 A052814 A151445 this_sequence A013989 A002841 
               A136509
%Y A000136 Adjacent sequences: A000133 A000134 A000135 this_sequence A000137 A000138 
               A000139
%K A000136 nonn
%O A000136 1,2
%A A000136 N. J. A. Sloane (njas(AT)research.att.com).