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A356380
Main diagonal of the LIRO variant of the array A035486; this is one of eight such sequences discussed in A007063.
2
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.
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
Sequence in context: A078064 A091517 A356376 * A106117 A081498 A110279
KEYWORD
nonn
AUTHOR
Clark Kimberling, Oct 24 2022
STATUS
approved