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A330006 Numbers m such that psi(m) > psi(k) for all k < m, where psi is the Dedekind psi function (A001615). 2
1, 2, 3, 4, 6, 10, 12, 18, 24, 30, 42, 54, 60, 78, 84, 90, 114, 120, 150, 168, 180, 210, 270, 294, 300, 330, 390, 420, 510, 546, 570, 630, 750, 780, 840, 990, 1050, 1170, 1260, 1470, 1650, 1680, 1890, 2100, 2310, 2730, 3150, 3360, 3570, 3990, 4290, 4620, 5250 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..808 (terms below 10^11)

FORMULA

A001615(a(n)) = A210523(n).

EXAMPLE

The first 6 values of the psi function are 1, 3, 4, 6, 6, 12. The record values, 1, 3, 4, 6, 12 are at positions 1, 2, 3, 4, 6.

MATHEMATICA

psi[1] = 1; psi[n_] := n * Times @@ (1 + 1/FactorInteger[n][[;; , 1]]); seq = {}; pmax = 0; Do[p = psi[n]; If[p > pmax, pmax = p; AppendTo[seq, n]], {n, 1, 10^5}]; seq

CROSSREFS

Cf. A001615, A210523 (record values).

Sequence in context: A249685 A343731 A181312 * A288784 A322164 A237823

Adjacent sequences:  A330003 A330004 A330005 * A330007 A330008 A330009

KEYWORD

nonn

AUTHOR

Amiram Eldar, Nov 26 2019

STATUS

approved

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Last modified June 13 22:55 EDT 2021. Contains 345016 sequences. (Running on oeis4.)