|
%I #6 Feb 19 2014 14:10:40
%S 2,3,4,5,6,7,6,5,4,3,2,1,2,3,4,5,6,7,8,7,6,5,4,3,2,3,4,5,6,7,8,7,6,5,
%T 4,3,2,1,2,3,4,5,6,7,8,7,6,5,4,3,2,3,4,5,6,7,8,7,6,5,4,5,6,7,8,9,8,7,
%U 6,5,4,3,2,1,0,1,2,3,4,5,4,3,2,3,4,5,4
%N A walk based on the digits of E = exp(1) (A001113).
%C E = 2.718281828459045...
%C Between 2 and 7 we place 3, 4, 5 and 6.
%C Between 7 and 1 we place 6, 5, 4, 3 and 2.
%C Between 1 and 8 we place 2, 3, 4, 5, 6 and 7.
%C Between 8 and 2 we place 7, 6, 5, 4 and 3, and so on.
%C This gives:
%C 2, 3, 4, 5, 6, 7, 6, 5, 4, 3, 2, 1, 2, 3, 4, 5, 6, 7, 8, 7, 6, 5, 4, ...
%C This could be called a walk (or promenade) on the digits of E.
%t wbe[{a_,b_}]:=Rest[If[b>a,Range[a,b],Range[a,b,-1]]]; Join[{2},Flatten[ wbe/@ Partition[RealDigits[E,10,20][[1]],2,1]]] (* _Harvey P. Dale_, Feb 19 2014 *)
%Y Cf. A001113
%K nonn,easy,base
%O 1,1
%A _Philippe Deléham_, Nov 20 2013 at the suggestion of _N. J. A. Sloane_
|
