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Table whose n-th row lists the prime factors of the n-th Giuga number A007850(n).
6

%I #7 Jul 14 2015 00:08:18

%S 2,3,5,2,3,11,13,2,3,7,41,2,3,11,17,59,2,3,11,23,31,47057,2,3,7,43,

%T 3041,4447,2,3,7,59,163,1381,775807,2,3,7,71,103,67213,713863,2,3,7,

%U 71,103,61559,29133437,2,3,11,23,31,47137,28282147,3892535183,2,3,11,23,31,47059,2259696349,110725121051,2,3,7,43,1831,138683,2861051,1456230512169437

%N Table whose n-th row lists the prime factors of the n-th Giuga number A007850(n).

%C It is unknown whether there are infinitely many Giuga numbers or any odd ones.

%C See A007850 for other comments, references, links, etc.

%C For prime factors of primary pseudoperfect numbers, see A236433; of terms in Sylvester's sequence, see A126263.

%H M. F. Hasler, <a href="/A236434/b236434.txt">Table of n, a(n) for n = 1..73</a>

%e 30 = 2 * 3 * 5.

%e 858 = 2 * 3 * 11 * 13.

%e 1722 = 2 * 3 * 7 * 41.

%e 66198 = 2 * 3 * 11 * 17 * 59.

%e 2214408306 = 2 * 3 * 11 * 23 * 31 * 47057.

%e 24423128562 = 2 * 3 * 7 * 43 * 3041 * 4447.

%e 432749205173838 = 2 * 3 * 7 * 59 * 163 * 1381 * 775807.

%e 14737133470010574 = 2 * 3 * 7 * 71 * 103 * 67213 * 713863.

%e 550843391309130318 = 2 * 3 * 7 * 71 * 103 * 61559 * 29133437.

%e 244197000982499715087866346 = 2 * 3 * 11 * 23 * 31 * 47137 * 28282147 * 3892535183.

%e 554079914617070801288578559178 = 2 * 3 * 11 * 23 * 31 * 47059 * 2259696349 * 110725121051.

%e 1910667181420507984555759916338506 = 2 * 3 * 7 * 43 * 1831 * 138683 * 2861051 * 1456230512169437.

%e Another Giuga number (but possibly not the 13th) is 4200017949707747062038711509670656632404195753751630609228764416142557211582098432545190323474818 = 2 * 3 * 11 * 23 * 31 * 47059 * 2217342227 * 1729101023519 * 8491659218261819498490029296021 * 58254480569119734123541298976556403.

%Y Cf. A007850, A216823, A216824, A236433.

%K nonn,tabf,hard

%O 1,1

%A _Jonathan Sondow_, Jan 25 2014