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A356377
Main diagonal of the ROLI variant of the array A035486; this is one of eight such sequences discussed in A007063.
2
1, 3, 5, 4, 8, 6, 10, 15, 2, 9, 13, 26, 11, 12, 33, 34, 35, 29, 22, 37, 44, 48, 56, 39, 43, 54, 36, 16, 23, 25, 76, 81, 47, 30, 42, 14, 72, 38, 74, 71, 68, 92, 77, 46, 69, 94, 78, 128, 45, 110, 89, 73, 135, 90, 62, 115, 101, 104, 85, 153, 113, 158, 171, 172
OFFSET
1,2
COMMENTS
Conjecture: every positive integer occurs exactly once.
MATHEMATICA
len = 8; roli = Join[{{1}}, NestList[Join[#[[Riffle[Range[Length[#], (Length[#] + 3)/2, -1], Range[(Length[#] - 1)/2, 1, -1]]]],
Range[#, # + 2] &[(3 Length[#] + 1)/2]] &, {2, 3, 4}, 200]];
s = Map[{#, Take[Flatten[Map[Take[#, {(Length[#] + 1)/2}] &, #]], 150] &[
ToExpression[#]]} &, {"roli"}];
Last[First[s]] (* A356377 *)
(* Peter J. C. Moses, Jul 26 2022 *)
(* The next program generates the ROLI array. *)
len = 8; roli = Join[{{1}}, NestList[Join[#[[Riffle[Range[Length[#], (Length[#] + 3)/2, -1], Range[(Length[#] - 1)/2, 1, -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[#]]]}]] &[roli]]
(* Peter J. C. Moses, Aug 02 2022 *)
CROSSREFS
Sequence in context: A069918 A361709 A200700 * A075380 A349374 A248497
KEYWORD
nonn
AUTHOR
Clark Kimberling, Oct 21 2022
STATUS
approved