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A343895
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Perimeters of integer-sided primitive triangles (a, b, c) where side a is the harmonic mean of the two other sides b and c, i.e., 2/a = 1/b + 1/c with b < a.
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1
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13, 37, 47, 71, 73, 107, 121, 143, 177, 181, 183, 191, 239, 241, 249, 253, 291, 299, 337, 347, 359, 409, 421, 429, 431, 433, 491, 517, 503, 529, 537, 541, 563, 579, 587, 649, 659, 661, 671, 743, 753, 759, 767, 769, 781, 789, 793, 831, 851, 897, 863, 913, 923, 933, 937, 947, 971, 1033
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OFFSET
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1,1
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COMMENTS
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This sequence is the list of ordered terms of A343894, which is not monotonic.
It first differs from A343894 at index 9 where a(9) = 177 while A343894(9) = 183.
For the corresponding primitive triples and miscellaneous properties and references, see A343891.
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LINKS
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EXAMPLE
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a(2) = 12 + 10 + 15 = 37, because the second largest perimeter corresponds to triple (12, 10, 15) with relations 2/12 = 1/10 + 1/15 and 15 - 10 < 12 < 15 + 10.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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