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A092864
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Greatest common divisor of triples a,b,c such that a < b < c, (a*b) mod (a+b) = c, (b*c) mod (b+c) = a, (c*a) mod (c+a) = b. The triples are ordered according to sum of first and second component.
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1
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1, 3, 3, 25, 5, 105, 8, 23, 25, 108, 96, 69, 204, 91, 19, 83, 145, 26, 225, 61, 77, 37, 107, 51, 9, 97, 133, 101, 49, 92, 23, 296, 67, 64, 345, 29, 161, 240, 109, 128, 27, 280, 107, 289, 53, 56, 151, 465, 235, 315, 91, 71, 43, 99, 72, 200, 26, 130, 49, 438, 57, 31, 227
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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The seventh triple is 184, 704, 776, hence a(7) = gcd(8*23,8*8*11,8*97) = 8.
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PROG
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(PARI) {m=4600; for(n=3, m, for(a=1, (n-1)\2, b=n-a; c=a*b%(a+b); if(b<c, if((b*c)%(b+c)==a, if((a*c)%(a+c)==b, print1(gcd(gcd(a, b), c), ", ")))))); }
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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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