(1896 - 1963)
    Nikola Obrechkoff was born in the town of Varna on March 6, 1896, in a large 8 children family, as the son of a military officer.

    His mathematical affiliation emerged in his teenage years when only sixteen years old he published his first work ``Expressing functions of an angle x/2 in terms of functions of x''.

    Obrechkoff graduated from the Mathematical Department of Sofia University in 1920. In 1922-1923 he was sent on a postgraduate specialization in Berlin. He got his first doctoral degree from the University of Palermo, Italy, in 1932. In 1933 Nikola Obrechkoff obtained a doctor of science degree (Docteur des sciences) from the Sorbonne, Paris. His second thesis ``Sur la sommation des séries divergentes'' was published in the most distinguished mathematical journal - Acta Mathematica, founded by Mittag Leffler.