In the years between the first edition of 1912 and the 2nd edition of 1927, H. M. Sheffer 1921 and M. Jean Nicod, nowadays known as the "stroke" or NAND (NOT-AND, NEITHER ... NOR...).
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Henry M. Sheffer (1921) and Jean Nicod is sufficient to express all propositional formulas.
Peter Sheffer, Jr, was the first non-Indian to be married west of the Genesee.