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CAP Cryptographic Analysis Program Anagram Help Presentation Press Enter or click on your mouse button to continue
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Use the mouse button to activate each presentation step 2 Breaking a Column Transposition Once you have a good estimate for the size of a column transposition you need to discover the correct arrangement of columns One tool that may help in this process in the Anagram tool provided by CAP It allows you to try to arrange the columns to produce words The place to begin is to look for rows that have letters that commonly belong together
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Use the mouse button to activate each presentation step 3 Letter Affinity First, in all languages there are certain letters usually of medium or low frequency which combine with other letters to form diagrams of high frequency H (medium frequency) combines with T to form TH (highest frequency) H combines with C (medium frequency) to form CH V (low frequency) combines with E to form VE (medium frequency in military text) Some possible RULES: When there is an H, attempts should be made to combine it with a T or a C A V should be combined first with an E A K should be combined first with a C
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Use the mouse button to activate each presentation step 4 Pilot Letters Second, there is usually in every language at least one letter which can be followed by only certain other letters forming an obligatory sequence or invariable digraph Q is always followed by U J can only be followed by a vowel X can be preceded only by a vowel and except at the end of a word can only be succeeded by a vowel or C, H, P, T Letters such as these with limited affinity are called pilot letters
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Use the mouse button to activate each presentation step 5 Centiban Scores For other possible letter pairs the Centiban table could be helpful The US government studied a set of 5,000 digrams and produced a table of what are called centiban weights This table contains the logarithm of twice the frequency of each digram A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A 33 45 61 73 13 38 45 25 64 13 25 76 61 89 25 58 00 82 80 83 59 48 33 00 58 00 B 38 00 00 00 66 00 00 00 25 13 00 45 13 00 38 00 00 25 13 13 25 00 00 00 48 00 C 67 00 33 13 76 13 00 61 48 00 38 42 13 13 80 00 00 38 13 61 38 00 13 00 13 00 D 76 38 38 51 77 51 25 25 73 13 00 33 42 38 63 42 25 58 59 62 42 33 38 00 13 00 E 78 38 76 88 81 66 38 48 73 13 00 74 61 99 58 67 58 94 86 79 33 67 48 48 38 13 F 42 00 25 13 55 56 13 00 80 00 00 25 13 00 80 13 00 53 33 56 33 00 13 00 13 00 G 48 00 25 13 61 25 13 67 42 13 00 25 13 33 45 25 00 42 33 38 25 00 13 00 00 00 H 67 13 33 25 67 42 00 00 77 00 00 13 25 33 67 13 13 64 38 74 51 00 13 00 13 00 I 51 25 69 45 59 55 67 00 00 00 25 70 53 92 80 48 00 73 78 73 00 72 00 62 00 25 J 18 00 00 00 25 00 00 00 00 00 00 00 00 00 25 00 00 00 00 00 25 00 00 00 00 00 K 13 00 13 00 45 00 00 00 25 00 00 13 00 13 00 00 00 00 13 00 00 00 00 00 00 00 L 74 33 33 53 79 33 13 13 67 00 00 73 25 13 59 33 00 25 45 51 25 25 25 00 55 00 M 78 45 33 13 72 13 00 13 53 00 00 00 59 00 55 51 00 25 38 25 25 00 00 00 25 00 N 72 25 67 85 87 53 73 38 75 13 25 42 42 51 66 33 13 38 71 93 48 33 33 00 42 00 O 48 38 51 58 33 72 25 33 42 13 25 67 72 92 45 72 00 89 61 67 79 48 51 13 25 00 P 61 13 13 13 70 25 00 33 45 00 00 59 38 13 64 56 00 66 45 51 33 13 13 00 13 00 Q 00 00 00 00 00 00 00 00 00 00 00 00 13 00 00 00 00 13 00 00 62 00 00 00 00 00 R 80 25 53 64 96 45 48 33 75 13 13 42 53 48 74 59 00 56 75 81 42 42 38 00 53 00 S 71 33 59 42 84 58 25 72 77 00 13 25 33 38 62 55 00 42 67 88 56 13 38 00 13 00 T 74 33 45 45 91 48 13 92 82 00 00 42 45 48 84 25 13 64 67 67 42 00 78 00 80 13 U 42 33 33 33 56 13 51 00 42 00 00 45 42 68 13 25 00 75 58 58 00 13 00 00 00 00 V 45 00 00 00 87 00 00 00 58 00 00 00 00 00 13 00 00 00 00 13 00 00 00 00 00 00 W 58 00 00 00 69 00 00 38 59 00 00 13 00 25 67 00 00 13 13 00 00 00 00 00 13 00 X 25 00 25 13 13 13 00 13 25 00 00 00 00 13 13 25 00 13 13 48 00 00 00 00 00 00 Y 45 25 38 38 53 56 13 13 33 00 00 25 25 45 55 33 00 38 56 62 13 00 13 00 00 00 Z 13 00 00 00 25 00 00 00 13 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Second Letter First LetterFirst Letter The higher the score the more likely the two letter should be paired
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