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A097014
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Smallest x such that sigma(x) mod 210 = n.
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5
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104, 1, 211, 2, 3, 8311689, 5, 4, 7, 3698, 399, 130321, 6, 9, 13, 8, 1477, 2458624, 10, 725904, 19, 676, 6751, 18766224, 14, 52707600, 489, 24649, 12, 220433409, 29, 16, 21, 1250, 2779, 3694084, 22, 5184, 37, 18, 27, 1382976, 20, 729, 43, 128, 217
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OFFSET
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0,1
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COMMENTS
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LINKS
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EXAMPLE
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Several numbers belonging to odd residues are either large squares or twice-squares.
E.g.: r = n = 209: a(209) = 36324729 = 6027^2, sigma(6027^2) = 210*172974 + 209.
Full set is easily available running through squares or twice squares.
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CROSSREFS
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KEYWORD
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fini,nonn
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AUTHOR
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STATUS
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approved
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