A356380 Main diagonal of the LIRO variant of the array A035486; this is one of eight such sequences discussed in A007063.

1, 3, 5, 6, 4, 11, 13, 2, 7, 14, 24, 9, 10, 31, 35, 33, 27, 23, 38, 42, 46, 54, 37, 44, 52, 34, 17, 21, 26, 77, 79, 45, 28, 40, 12, 70, 36, 72, 69, 66, 90, 75, 47, 67, 95, 76, 126, 43, 108, 87, 74, 133, 88, 60, 116, 99, 102, 86, 151, 111, 156, 169, 173, 171

Offset

1,2

Comments

Conjecture: every positive integer occurs exactly once.

Links

Table of n, a(n) for n=1..64.

Mathematica

lori = Join[{{1}}, NestList[Join[#[[Riffle[Range[1, (Length[#] - 1)/2],
      Range[(Length[#] + 3)/2, Length[#]]]]],
      Range[#, # + 2] &[(3 Length[#] + 1)/2]] &, {2, 3, 4}, 200]];
s = Map[{#, Take[Flatten[Map[Take[#, {(Length[#] + 1)/2}] &, #]], 150] &[
      ToExpression[#]]} &, {"lori"}];
Last[First[s]]   (* A356379 *)
(* Peter J. C. Moses, Jul 26 2022 *)
(* The next program generates the LIRO array. *)
len = 8; liro = Join[{{1}}, NestList[Join[#[[Riffle[Range[(Length[#] - 1)/2, 1, -1],
     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[#]]]}]] &[liro]]
(* Peter J. C. Moses, Aug 02 2022 *)

Crossrefs

Cf. A007063, A035486.

Sequence in context: A078064 A091517 A356376 * A106117 A081498 A110279

Adjacent sequences: A356377 A356378 A356379 * A356381 A356382 A356383

Keyword

nonn

Author

Clark Kimberling, Oct 24 2022

Status

approved