------------------------------------------------------------------ A060950 a(n) is rank of elliptic curve y^2=x^3+n 0 1 1 0 1 0 0 1 1 1 1 1 0 0 2 0 2 1 1 0 0 1 0 2 0 1 0 1 0 1 1 0 1 0 1 1 2 1 1 1 1 0 2 1 0 1 1 1 0 1 0 1 0 1 1 1 2 1 0 0 1 1 2 0 2 1 1 1 1 0 1 1 2 1 0 1 1 0 2 1 0 1 1 0 0 0 0 0 2 0 1 1 0 1 0 0 1 1 1 1 2 1 1 0 1 2 1 1 0 1 1 1 3 0 0 0 1 1 1 1 1 2 ? 0 0 1 1 1 2 1 2 1 1 1 0 1 0 1 1 0 3 2 1 0 2 1 1 2 1 1 2 1 0 1 1 1 0 0 0 0 2 0 1 2 0 1 0 2 1 1 2 1 0 ? 0 0 1 0 1 0 0 1 1 1 1 2 0 1 1 1 1 1 0 0 2 1 2 2 1 0 0 1 0 2 1 1 1 1 0 1 1 1 1 ? 1 0 2 1 1 1 1 2 2 1 2 1 1 0 2 0 ? 2 2 1 1 1 0 1 0 0 1 0 0 0 0 1 1 2 1 0 1 2 0 1 1 0 1 0 0 2 0 1 1 1 2 0 0 2 2 0 1 1 0 1 1 1 1 1 0 1 2 1 1 0 1 ? 1 1 1 1 1 0 1 2 2 1 2 1 1 0 0 0 2 0 0 0 1 0 0 1 0 0 1 1 1 3 0 1 1 1 1 2 1 0 1 1 1 1 1 0 2 1 1 1 1 1 2 0 0 1 0 1 1 1 0 3 2 0 1 2 1 1 2 1 1 1 1 0 3 2 0 ? 0 1 1 2 0 1 2 1 1 0 2 0 0 0 2 0 1 1 2 1 ? 0 1 1 0 2 2 1 1 2 1 0 1 1 0 1 1 0 1 0 0 2 1 1 1 1 2 0 0 2 0 2 1 1 0 1 0 1 1 1 1 1 1 1 3 0 1 0 1 0 2 1 1 0 1 0 0 1 1 1 3 1 ? 0 0 0 2 0 1 0 0 1 0 0 1 1 0 1 0 1 1 2 1 0 1 1 2 1 1 1 1 0 1 1 0 1 1 1 2 0 2 0 2 1 ? 1 0 1 0 2 1 1 0 1 0 1 1 1 Notes: n up to 500 are shown. Entries of '?' at n=123,174,214,231,286,362, 383,445,487 indicate that the rank is either unknown or conjectural, but is known to be either 1 or 2 or 3. All numbers above have been extracted from: H. Mishima, Tables of Elliptic Curves (http://www.asahi-net.or.jp/~KC2H-MSM/ec/eca1/ec01rp.txt ), except for n=274, for which Ian Connell's APECS gives unconditionally a(274)=1. ------------------------------------------------------------------------