Supporting data, regarding 'An expansion method for calculating atomic properties X. 1s2 1S-1snp 1P transitions of the helium sequence' by Alexander Dalgarno and E M Parkinson A table, labelled table 1, of numerical data, followed by an appendix labelled 'Algebraic form of the functions occurring in equations (34) and (36)'. Annotations in ink. Subject: Mathematics The affiliated paper was published in volume 301 of the Proceedings of the Royal Society as 'An expansion method for calculating atomic properties X. 1s2 1S-1snp 1P transitions of the helium sequence'. [1967]