Allan Joseph Champneys Cunningham

The British mathematician Allan Joseph Champneys Cunningham (Delhi 1842 – London 1928) started a military career with the East India Company's Bengal (later Royal) Engineers. During 1871–1881, he was Instructor in Mathematics at the Thomason Civil Engineering College, Roorkee. Upon returning to the United Kingdom in 1881, he continued teaching at military institutes in Chatham, Dublin and Shorncliffe. He left the army in 1891.

He spent the rest of his life studying number theory. He applied his expertise to finding factors of large numbers of the form aⁿ ± bⁿ, such as Mersenne numbers (${\displaystyle 2^{p}-1}$) and Fermat numbers (${\displaystyle 2^{2^{n}}+1}$) which have b = 1. His work is continued in the Cunningham project.

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