A306035 Indices of records in A305382.

1, 10, 13, 16, 22, 24, 64, 140, 198, 473, 1163, 3936, 5573, 9356, 13496, 13927, 17048, 134497, 194752, 283870, 630705, 1468682, 5365535, 7863153, 10531772, 11682803, 92922963, 99080899, 145711608, 214374183, 3388736774

Offset

1,2

Comments

Where records occur in A305382.

Links

Table of n, a(n) for n=1..31.

Mathematica

With[{s = Array[Length@ NestWhile[Union@ Join[#, First /@ Flatten[FactorInteger[2 # + 1], 1]] &, {Prime@ #}, UnsameQ, All] &, 10^5]}, Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s] ] ] (* Michael De Vlieger, Jul 06 2018, after Robert G. Wilson v at A305382 *)

Crossrefs

Cf. A305382, A316226.

Sequence in context: A153045 A055984 A282108 * A339077 A373278 A335016

Adjacent sequences: A306032 A306033 A306034 * A306036 A306037 A306038

Keyword

nonn

Author

Hans Havermann, Jun 17 2018

Status

approved