cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A253881 Positive integers N such that rational Diophantine triple {-1/N, N, (N^2-1)/N} can be extended to a quadruple.

Original entry on oeis.org

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

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Author

Thomas Bokk, Jan 17 2015

Keywords

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.