Calculator to the development of electronic calculators. The Casio Computer Company, in Japan, released the Model "14-A" calculator in 1957, which was the world's first all-electric (relatively) compact calculator. It did not use electronic logic but was based on relay technology, and was built into a desk. In October 1961, the world's first "all-electronic desktop" calculator, the British Bell Punch/Sumlock Comptometer ANITA (A New Inspiration To Arithmetic/Accounting) was announced. This machine used vacuum tubes, cold-cathode tubes and Dekatrons in its circuits, with 12 cold-cathode "Nixie" tubes for its display. Two models were displayed, the Mk VII for continental Europe and the
Inverse Symbolic Calculator of the tables with 3.702 billion entries (as of June 19, 2010) exists. In 2016, Plouffe released a portable version of Plouffe's Inverter containing 3 billion entries. Inverse Symbolic Calculator The Inverse Symbolic Calculator is an online number checker established July 18, 1995 by Peter Benjamin Borwein, Jonathan Michael Borwein and Simon Plouffe of the Canadian Centre for Experimental and Constructive Mathematics (Burnaby, Canada). A user will input a number and the Calculator will use an algorithm to search for and calculate closed-form expressions or suitable functions that have roots near this number. Hence, the calculator is of great importance