The multi-planet system TOI-421 -- A warm Neptune and a super puffy mini-Neptune transiting a G9 V star in a visual binary

KESPRINT collaboration, an international consortium devoted to the characterization and research of exoplanets discovered with space-based missions \r\nNASA\u0027s Science Mission directorate \r\nNASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center \r\nNational Aeronautics \u0026 Space Administration (NASA)\r\n\r\n \r\nEuropean Research Council (ERC)\r\n\r\n817540\r\nEuropean Research Council under the European Union\u0027s Horizon 2020 research and innovation program \t\r\n832428\r\nCRT foundation \t\r\n2018.2323\r\nComision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)\r\n\r\nCONICYT FONDECYT\r\n\r\n3180246\r\nMillennium Science Initiative, Chilean Ministry of Economy \t\r\nIC120009\r\nComision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)\r\n\r\nCONICYT FONDECYT\r\n\r\n1171208\r\nIrish Research Council for Science, Engineering and Technology\r\n\r\nGOIPD/2018/659\r\nSwedish National Space Agency \t\r\nDNR 65/19\r\n136/13\r\nAustralian Research Council\r\n\r\n170100521\r\nNASA through Caltech/JPL grant \t\r\nRSA-1006130\r\nNASA through TESS Guest Investigator Program \t\r\n80NSSC19K1727\r\nAlfred P. Sloan Foundation\r\n\r\n \r\nNational Aeronautics \u0026 Space Administration (NASA)\r\n\r\n80NSSC18K1585\r\n80NSSC19K0379\r\nNational Science Foundation (NSF)\r\n\r\nAST1717000\r\nSpanish Government\r\n\r\nRYC-2015-17697\r\nFPI-SO from the Spanish Ministry of Economy and Competitiveness (MINECO) \t\r\nSEV-2015-0548-17-2\r\nBES-2017-082610\r\nNational Aeronautics \u0026 Space Administration (NASA)\r\n\r\nNNX17AF27G\r\nHeisingSimons foundation \r\nPLATO grant \r\nGOLF CNES grant \r\nCONICYT-PFCHA/Doctorado Nacional, Chile \t\r\n21140646\r\nGerman Research Foundation (DFG)\r\n\r\nPA525/18-1\r\nPA525/19-1\r\nPA525/20-1\r\nHA3279/12-1\r\nRA714/14-1\r\nNational Aeronautics \u0026 Space Administration (NASA)