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A088825 Numbers n such that the sum of largest prime factors of numbers from 1 to n is divisible by n. 4
1, 2, 8, 9, 32, 62, 558, 993, 995, 1947, 2150, 4343, 9944, 10977, 43054658, 202275890, 2291937393, 2459073795, 2836929091, 3737529738, 21382629569, 248208997602, 389691028017, 838566394212, 1019000924619 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(21) > 15*10^9. - Donovan Johnson, Nov 01 2009

a(22) > 10^11. - Donovan Johnson, Jul 09 2010

a(26) > 5*10^12. - Giovanni Resta, Apr 25 2017

LINKS

Table of n, a(n) for n=1..25.

FORMULA

Solutions to Mod[A088822[x], x]=0.

MATHEMATICA

gp[n_] := If[n==1, 0, FactorInteger[n][[-1, 1]]]; Flatten@ Position[ Accumulate[ gp /@ Range[10^5]] / Range[10^5], _Integer] (* Giovanni Resta, Apr 25 2017 *)

CROSSREFS

Cf. A088821-A088824.

Sequence in context: A163619 A166968 A075644 * A337706 A181887 A221049

Adjacent sequences:  A088822 A088823 A088824 * A088826 A088827 A088828

KEYWORD

nonn

AUTHOR

Labos Elemer, Oct 22 2003

EXTENSIONS

More terms from Ray Chandler, Oct 31 2003

a(17)-a(20) from Donovan Johnson, Nov 01 2009

a(21) from Donovan Johnson, Jul 09 2010

a(22)-a(25) from Giovanni Resta, Apr 25 2017

STATUS

approved

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Last modified April 16 07:59 EDT 2021. Contains 343030 sequences. (Running on oeis4.)