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A106128 Numbers k such that the k-th semiprime == 3 (mod k). 1
1, 3, 6, 36, 46, 78, 6915, 6916, 613375, 613378, 613404, 613406, 613414, 613438, 613448, 613454, 613456, 613508, 613519, 613522, 613532, 613559, 613568, 613570, 613582, 613586, 613598, 58155528, 58155536, 58155549, 6384425454, 6384425520, 6384425522, 6384425528, 6384425638 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Lucas A. Brown, Table of n, a(n) for n = 1..47

EXAMPLE

a(3) = 6 is a term because the 6th semiprime is 15 and 15 == 3 (mod 6).

CROSSREFS

Cf. A001358.

Sequence in context: A184390 A130317 A019467 * A119186 A119115 A079653

Adjacent sequences:  A106125 A106126 A106127 * A106129 A106130 A106131

KEYWORD

hard,nonn

AUTHOR

Shyam Sunder Gupta, May 07 2005

EXTENSIONS

a(28)-a(30) from Donovan Johnson, Oct 29 2008

a(1), a(2), and a(31)-a(47) by Lucas A. Brown, Oct 19 2020

STATUS

approved

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Last modified October 22 05:36 EDT 2021. Contains 348160 sequences. (Running on oeis4.)