Search results
Results from the WOW.Com Content Network
The VIC cipher can be regarded as the evolutionary pinnacle of the Nihilist cipher family.. The VIC cipher has several important integrated components, including mod 10 chain addition, a lagged Fibonacci generator (a recursive formula used to generate a sequence of pseudorandom digits), a straddling checkerboard, and a disrupted double transposition.
Suppose a standard 8×8 chessboard (or checkerboard) has two diagonally opposite corners removed, leaving 62 squares. Is it possible to place 31 dominoes of size 2×1 so as to cover all of these squares? It is an impossible puzzle: there is no domino tiling meeting these conditions. One proof of its impossibility uses the fact that, with the ...
In the second step, they were divided by 3. The final result, 4 / 3 , is an irreducible fraction because 4 and 3 have no common factors other than 1. The original fraction could have also been reduced in a single step by using the greatest common divisor of 90 and 120, which is 30. As 120 ÷ 30 = 4, and 90 ÷ 30 = 3, one gets
6 1 2 1 1 −1 4 5 9. and would be written in modern notation as 6 1 / 4 , 1 1 / 5 , and 2 − 1 / 9 (i.e., 1 8 / 9 ). The horizontal fraction bar is first attested in the work of Al-Hassār (fl. 1200), [35] a Muslim mathematician from Fez, Morocco, who specialized in Islamic inheritance jurisprudence.
The length of the grid's last line is given by the remainder. The key is written above the grid, and the ciphertext is written down the columns of the grid in the order given by the letters of the key. The plaintext appears on the rows. A partial decipherment of the above ciphertext, after writing in the first column: 6 3 2 4 1 5 . . . . E ...
The Polybius square, also known as the Polybius checkerboard, is a device invented by the ancient Greeks Cleoxenus and Democleitus, and made famous by the historian and scholar Polybius. [1] The device is used for fractionating plaintext characters so that they can be represented by a smaller set of symbols, which is useful for telegraphy ...
Other slight variants, also incorporating seriation, are described in Schick (1987) [10] and David (1996). [11]The two-square cipher is not described in some other 20th century popular cryptography books e.g. by Helen Fouché Gaines (1939) or William Maxwell Bowers (1959), although both describe the Playfair cipher and four-square cipher.
Arrangements of Conway's soldiers to reach rows 1, 2, 3 and 4. The soldiers marked "B" represent an alternative to those marked "A". Conway's Soldiers or the checker-jumping problem is a one-person mathematical game or puzzle devised and analyzed by mathematician John Horton Conway in 1961.