Specialization at T = 1634/921 of a rank-17 fibration of X1152 not posted before: y^2 = x^3 + A4 x + A6, where
A4 = -94521237307405223348592T^8 + 194603007768925915807776T^7 + 374678018163025368194124T^6 - 569211691896707346596088T^5 + 55463370301014723924120T^4 - 1135612908646444410668928T^3 - 2702507543729482509654336T^2 + 609092474805433024526016T - 184694377125002807554992,
A6 = 11265741534554236438342976060251776T^12 - 34833166213267258548363680994916992T^11 - 69502033189823387959197312852122064T^10 + 265587490260133017697161120524802480T^9 + 273144084685427886803017231992231060T^8 - 1114854493674664679669934784078225824T^7 - 766273999597311933358466543970856272T^6 + 2407762999977059159006184076291662816T^5 + 1357060199643920217443950358505612000T^4 - 540509467373796107556447739286515200T^3 + 808090270114106954000628418781159424T^2 - 154315127645781466989761857773289728T + 30433563297067405810172392059479424.
It is a 2-neighbour of the fibration given in curve#3900: its Mordell-Weil lattice (rank 17, no reducible fibres) is a root-free Kneser 2-neighbour of that fibration's, realised by the pencil |O + P - F| for a section P of height 12. Constructed and searched by Claude (Anthropic): a Mestre-Nagao sieve over the fibration, then a 2-covering point search seeded with its generic sections.
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