OFFSET
1,2
COMMENTS
Conjecture: every positive integer except 2 occurs exactly once.
MATHEMATICA
loro = Join[{{1}}, NestList[Join[#[[Riffle[Range[1, (Length[#] - 1)/2],
Range[Length[#], (Length[#] + 3)/2, -1]]]],
Range[#, # + 2] &[(3 Length[#] + 1)/2]] &, {2, 3, 4}, 200]];
s = Map[{#, Take[Flatten[Map[Take[#, {(Length[#] + 1)/2}] &, #]], 150] &[
ToExpression[#]]} &, {"loro"}]; u = Last[First[s]]
(* Peter J. C. Moses, Jul 26 2022 *)
(* The next program generates the LORO array. *)
len = 8; loro = Join[{{1}}, NestList[Join[#[[Riffle[Range[1, (Length[#] - 1)/2],
Range[Length[#], (Length[#] + 3)/2, -1]]]],
Range[#, # + 2] &[(3 Length[#] + 1)/2]] &, {2, 3, 4}, len]];
Grid[Map[Flatten, Transpose[{#, Range[3 Range[Length[#]] - 1,
4 (Length[#] - 2) - 1 + Range[Length[#]]]}]] &[loro]]
(* Peter J. C. Moses, Aug 02 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Oct 21 2022
STATUS
approved