OFFSET
1,2
COMMENTS
Conjecture: every positive integer occurs exactly once.
MATHEMATICA
rilo = Join[{{1}}, NestList[Join[#[[Riffle[Range[(Length[#] + 3)/2, Length[#]], Range[1, (Length[#] - 1)/2, 1]]]], Range[#, # + 2] &[(3 Length[#] + 1)/2]] &, {2, 3, 4}, 200]]; (* A356378 *)
s = Map[{#, Take[Flatten[Map[Take[#, {(Length[#] + 1)/2}] &, #]], 150] &[
ToExpression[#]]} &, {"rilo"}];
Last[First[s]] (* A356378 *)
(* Peter J. C. Moses, Jul 26 2022 *)
(* The next program generates the RILO array. *)
len = 8; rilo = Join[{{1}}, NestList[Join[#[[Riffle[Range[(Length[#] + 3)/2, Length[#]],
Range[1, (Length[#] - 1)/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[#]]]}]] &[rilo]]
(* Peter J. C. Moses, Aug 02 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Oct 21 2022
STATUS
approved