A362454 - OEIS

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A362454

Indices of 1's in A361897.

1, 2, 3, 5, 6, 7, 12, 17, 18, 19, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 48, 65, 66, 67, 69, 70, 71, 76, 84, 88, 92, 97, 98, 99, 101, 102, 103, 108, 113, 114, 115, 117, 118, 119, 124, 128, 129, 130, 131, 133, 134, 135, 140, 144, 145, 146, 147, 149, 150, 151, 153, 154, 155, 157, 158

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Paolo Xausa, Table of n, a(n) for n = 1..20000 (terms 1..4750 from N. J. A. Sloane)

MATHEMATICA

A362454[upto_]:=Module[{d=DivisorSigma[0, Range[upto]]}, Join[{1}, Table[If[First[d=Abs[Differences[d]]]==1, n, Nothing], {n, 2, upto}]]]; A362454[200] (* Paolo Xausa, May 07 2023 *)

CROSSREFS

Cf. A361897, A362450, A362453.

Sequence in context: A189208 A270974 A039058 * A046158 A070274 A088968

Adjacent sequences: A362451 A362452 A362453 * A362455 A362456 A362457

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, May 05 2023

STATUS

approved