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A164326 a(n) is the smallest number m such that (2k-1)m - 1 is prime for all 0 < k < n+1. 1
3, 4, 4, 6, 6, 2100, 2100, 105828450, 3533468190, 240544635660, 7392639784530, 1896344521244250, 5389539504929580, 68086992545221650 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..14.

MATHEMATICA

a[n_] := Block[{k=1}, While[! AllTrue[k  Range[1, 2 n - 1, 2] - 1, PrimeQ], k++]; k]; Array[a, 7] (* Giovanni Resta, Apr 01 2017 *)

CROSSREFS

Cf. A071576, A164325.

Sequence in context: A120613 A277193 A240728 * A117571 A008474 A111611

Adjacent sequences:  A164323 A164324 A164325 * A164327 A164328 A164329

KEYWORD

more,nonn

AUTHOR

Farideh Firoozbakht, Sep 16 2009

EXTENSIONS

a(10) from Zak Seidov, Sep 21 2009

a(11)-a(14) from Giovanni Resta, Mar 31 2017

STATUS

approved

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Last modified September 20 16:09 EDT 2017. Contains 292276 sequences.