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 A236434 Table whose n-th row lists the prime factors of the n-th Giuga number A007850(n). 6
 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, 3041, 4447, 2, 3, 7, 59, 163, 1381, 775807, 2, 3, 7, 71, 103, 67213, 713863, 2, 3, 7, 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS It is unknown whether there are infinitely many Giuga numbers or any odd ones. See A007850 for other comments, references, links, etc. For prime factors of primary pseudoperfect numbers, see  A236433; of terms in Sylvester's sequence, see A126263. LINKS M. F. Hasler, Table of n, a(n) for n = 1..73 EXAMPLE 30 = 2 * 3 * 5. 858 = 2 * 3 * 11 * 13. 1722 = 2 * 3 * 7 * 41. 66198 = 2 * 3 * 11 * 17 * 59. 2214408306 = 2 * 3 * 11 * 23 * 31 * 47057. 24423128562 = 2 * 3 * 7 * 43 * 3041 * 4447. 432749205173838 = 2 * 3 * 7 * 59 * 163 * 1381 * 775807. 14737133470010574 = 2 * 3 * 7 * 71 * 103 * 67213 * 713863. 550843391309130318 = 2 * 3 * 7 * 71 * 103 * 61559 * 29133437. 244197000982499715087866346 = 2 * 3 * 11 * 23 * 31 * 47137 * 28282147 * 3892535183. 554079914617070801288578559178 = 2 * 3 * 11 * 23 * 31 * 47059 * 2259696349 * 110725121051. 1910667181420507984555759916338506 = 2 * 3 * 7 * 43 * 1831 * 138683 * 2861051 * 1456230512169437. Another Giuga number (but possibly not the 13th) is 4200017949707747062038711509670656632404195753751630609228764416142557211582098432545190323474818 = 2 * 3 * 11 * 23 * 31 * 47059 * 2217342227 * 1729101023519 * 8491659218261819498490029296021 * 58254480569119734123541298976556403. CROSSREFS Cf. A007850, A216823, A216824, A236433. Sequence in context: A060084 A265668 A273087 * A138182 A167835 A102044 Adjacent sequences:  A236431 A236432 A236433 * A236435 A236436 A236437 KEYWORD nonn,tabf,hard AUTHOR Jonathan Sondow, Jan 25 2014 STATUS approved

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Last modified April 8 15:38 EDT 2020. Contains 333314 sequences. (Running on oeis4.)