Use Thread to make a list of rules with each letter of the alphabet going to its position in the alphabet.

30.1

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Make a 4×6 grid of the first 24 letters of the alphabet.

30.2

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Make a grid of the digits in 2^1000, with 50 digits per row, and put frames around everything.

30.3

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Make a grid of the first 400 characters in the Wikipedia article for “computers”, with 20 characters per row, and frames around everything.

30.4

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Make a line plot of the flattened list of the digits from the numbers from 0 to 200 (Champernowne sequence).

30.5

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Make 4 steps in the “Menger sponge” analog of the fractal Sierpinski pattern from the text, but with a “kernel” of the form {{#,#,#},{#,0,#},{#,#,#}}.

30.6

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Find Pythagorean triples involving only integers by selecting {x,y,Sqrt[x^2+y^2]} with x and y up to 20.

30.7

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Find the lengths of the longest sequences of identical digits in 2^n for n up to 100.

30.8

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Take the names of integers up to 100 and gather them into sublists according to their first letters.

30.9

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Sort the first 50 words in WordList[ ] by their last letters.

30.10

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Make a list of the first 20 squares, sorted by their first digits.

30.11

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Sort integers up to 20 by the length of their names in English.

30.12

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Get a random sample of 20 words from WordList[ ], and gather them into sublists by length.

30.13

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Find letters that appear in Ukrainian but not Russian.

30.14

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Use Intersection to find numbers that appear both among the first 100 squares and cubes.

30.15

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Find the list of countries that are in both NATO and the G8.

30.16

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Make a grid in which all possible permutations of the numbers 1 through 4 appear as successive columns.

30.17

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Make a list of all the different strings that can be obtained by permuting the characters in “hello”.

30.18

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Make an array plot of the sequence of possible 5-tuples of 0 and 1.

30.19

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Generate a list of 10 random sequences of 5 letters.

30.20

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Find a simpler form for Flatten[Table[{i,j,k},{i,2},{j,2},{k,2}],2].

30.21

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Make an array plot from the numbers of the letters in the first 1000 characters in the Wikipedia article on “computers”, with 30 letters per row.

x30.1

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Gather integers up to 30 into lists based on their values modulo 3.

x30.2

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Gather the first 50 powers of 2 according to their last digits.

x30.3

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Make a line plot of the result of sorting the numbers from −10 to +10 by their absolute values.

x30.4

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Make a line plot of the list of the first 200 squares, sorted by their first digits.

x30.5

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Make a line plot of integers up to 200 sorted by the lengths of their names in English.

x30.6

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Get a random sample of 25 words from WordList[].

x30.7

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Riffle periods into the string “UNCLE” to make “U.N.C.L.E.”.

x30.8

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Find letters that appear in Swedish or Polish but not English.

x30.9

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Find countries that are in the World Health Organization but not the United Nations.

x30.10

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Make a list of all pair-wise blends of red, green and blue.

x30.11

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Make a list of array plots, each 50 rows high and with image size 50, of successive possible 8-tuples of 0 and 1.

x30.12

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Generate 1000 random sequences of 4 letters, and make a list of ones that appear in WordList[ ].

x30.13

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