A343136 Positions of records in A188171.

1, 5, 45, 315, 585, 2205, 2925, 9945, 17325, 28665, 45045, 135135, 225225, 405405, 675675, 1576575, 2027025, 2297295, 3828825, 6891885, 11486475, 26801775, 34459425, 43648605, 72747675, 130945815, 218243025, 509233725, 654729075, 1003917915, 1527701175, 3011753745, 4583103525

Offset

1,2

Links

Table of n, a(n) for n=1..33.

Example

585 is in the sequence as A188171(585) = 4 via the divisors 5, 13, 45 and 117 and no positive integer < 585 has at least four such (5 (mod 8)) divisors.

Mathematica

Function[{s, r}, Map[FirstPosition[s, #][[1]] &, r]] @@ {#, Union@ FoldList[Max, #]} &@ Array[DivisorSum[#, 1 &, Mod[#, 8] == 5 &] &, 10^6] (* Michael De Vlieger, Apr 08 2021 *)

Crossrefs

Cf. A188171, A343106.

Sequence in context: A302526 A303408 A241275 * A343106 A081070 A247494

Adjacent sequences: A343133 A343134 A343135 * A343137 A343138 A343139

Keyword

nonn

Author

David A. Corneth, Apr 06 2021

Status

approved