

A124492


a(n) = least k such that 2*i*k  1 is prime for 1 <= i <= n.


7



2, 2, 2, 3, 3, 77385, 1447110, 1447110, 203937090, 107290072890, 4724240531010, 123618251967210, 1272603355923900, 9089306184994125090
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OFFSET

1,1


LINKS

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


MATHEMATICA

a[n_] := Block[{k = If[n < 6, 1, 5], s}, s = k; While[! AllTrue[k 2 Range[n]  1, PrimeQ], k += s]; k]; Array[a, 8] (* Giovanni Resta, Apr 01 2017 *)


CROSSREFS

Cf. A006254, A124485A124491, A071576.
Sequence in context: A082861 A131704 A327746 * A338629 A057646 A238892
Adjacent sequences: A124489 A124490 A124491 * A124493 A124494 A124495


KEYWORD

nonn,more


AUTHOR

Artur Jasinski, Nov 04 2006


EXTENSIONS

Corrected and extended by Don Reble, Nov 05 2006
a(12)a(14) from Giovanni Resta, Apr 01 2017


STATUS

approved



