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A253881
Positive integers N such that rational Diophantine triple {-1/N, N, (N^2-1)/N} can be extended to a quadruple.
0
9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 29, 31, 33, 34, 37, 40, 41, 43, 45, 46, 48, 49, 50, 51, 52, 54, 55, 56, 57, 60, 61, 62, 65, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78, 79, 80, 81, 83, 84, 85, 86, 88, 91, 93, 95, 96, 97, 99, 103, 105, 106, 111, 113, 114, 115, 117, 119
OFFSET
1,1
COMMENTS
Positive integer N belongs to this sequence if and only if the elliptic curve y^2 = x^3 + (N^2+1/N^2)*x^2 + x has positive rank.
CROSSREFS
Sequence in context: A173147 A342145 A293761 * A097480 A034068 A045550
KEYWORD
nonn
AUTHOR
Thomas Bokk, Jan 17 2015
STATUS
approved