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A262873
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Predestined numbers A262743 in which every term is generated by at least one pair of products where all (and only those) first product's factor's digits are, in reverse order, the same as those of the second two factors.
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3
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504, 756, 806, 868, 1008, 1148, 1176, 1209, 1472, 1475, 1512, 1638, 1708, 2016, 2184, 2208, 2418, 2548, 2730, 2772, 2924, 3024, 3388, 4416
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OFFSET
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1,1
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COMMENTS
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In this sequence, the position of the multiplication sign in the reversed order is irrelevant, so, e.g., 11088 (48*231 and 132*84), 1176 (4*294 and 49*24) and 2548 (4*637 and 7*364) are in the sequence.
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REFERENCES
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Francesco Di Matteo, Sequenze ludiche, Game Edizioni (2015), page 34.
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LINKS
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EXAMPLE
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504 = 12*42 = 24*21;
756 = 12*63 = 36*21;
806 = 13*62 = 26*31;
868 = 4*217 = 7*124;
1008 = 12*84 = 48*21;
1148 = 14*82 = 28*41;
1176 = 4*294 = 49*24, etc.
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CROSSREFS
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Cf. A228164 (contains only symmetrical digits' factors)
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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