A300156 Indices of records in A299990.

1, 30, 42, 66, 78, 90, 102, 114, 138, 150, 210, 330, 390, 510, 570, 630, 870, 990, 1050, 1470, 1890, 2100, 2310, 2730, 3570, 3990, 4620, 5460, 6510, 6930, 8190, 9240, 10710, 11550, 13650, 16170, 19110, 20790, 23100, 24570, 25410, 30030, 39270, 43890, 46410

Offset

1,2

Comments

A010846(n) = A000005(n) + A243822(n).

Successive terms in this sequence represent increasing differences A243822(n) - A000005(n).

A000079 = records in -1 * A299990, since A243822(p^e)=0 for e>=0, n = 2^k sets records in A000005(n). The corresponding records are in A000027.

Links

Michael De Vlieger, Table of n, a(n) for n = 1..108

Michael De Vlieger, Relationships between A244052, A294492, and A300156.

Example

The first term is 1: A299990(1) = -1. The first term that exceeds -1 in A299990 corresponds to n = 30; A299990(30) = 2, thus 30 is the second term.

Mathematica

With[{s = Table[Count[Range[n], _?(PowerMod[n, Floor@ Log2@ n, #] == 0 &)] - 2 DivisorSigma[0, n], {n, 10^3}]}, Map[FirstPosition[s, #][[1]] &, Union@ FoldList[Max, s]]]

Crossrefs

Cf. A000005, A000027, A000079, A010846, A243822, A299990, A299991, A299992, A300155, A300157.

Sequence in context: A189759 A046401 A302570 * A306330 A160352 A291446

Adjacent sequences: A300153 A300154 A300155 * A300157 A300158 A300159

Keyword

nonn

Author

Michael De Vlieger, Feb 26 2018

Status

approved