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A322374 Where records occur in A322373. 1
1, 6, 12, 30, 60, 120, 180, 360, 420, 720, 840, 1260, 2520, 5040, 7920, 9240, 13860, 18480, 25200, 27720, 50400, 55440, 83160, 110880, 138600, 163800, 166320, 240240, 277200, 327600, 332640, 360360, 554400, 720720, 1081080, 1413720, 1441440, 1801800, 2162160, 2827440 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

The divisors of 6 are {1, 2, 3, 6} and gcd(3, 6) = 3 > 1 but gcd(2, 3, 6) = 1. As 2 is the second divisor of 6, A322373(6) = 2. This is a new record; A322373(k) < 2 for all k < 6. Therefore, 6 is in the sequence.

MATHEMATICA

With[{s = Array[LengthWhile[#, # == 1 &] &@ Reverse@ FoldList[GCD[#1, #2] &, Reverse@ Divisors@ #] &, 10^6]}, Map[First@ FirstPosition[s, #] &, Union@ FoldList[Max, s]]] (* Michael De Vlieger, Dec 31 2018 *)

PROG

upto(n) = my(r=0, res=List()); for(i=1, n, c=A322373(i); if(c > r, listput(res, i); print1(i", "); r = c)); res \\ David A. Corneth, Dec 09 2018

CROSSREFS

Cf. A322373.

Sequence in context: A036690 A229746 A256579 * A014131 A236539 A122211

Adjacent sequences:  A322371 A322372 A322373 * A322375 A322376 A322377

KEYWORD

nonn

AUTHOR

David A. Corneth, Dec 09 2018

STATUS

approved

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Last modified April 13 06:02 EDT 2021. Contains 342935 sequences. (Running on oeis4.)