# Monthly Archives: January 2012

## Concatenation of Num3ers: (a(2n+1)+a(2n))^2 = a(2n+1) a(2n)

In mathematics, concatenation is the joining of two numbers by their numerals. That is, the concatenation of 123 and 456 is 123456. Concatenation of numbers a and b is denoted a||b. Here are examples of quite remarkable numbers: 494 + … Continue reading

## Why is 1+1=2 on the 20 greatest equation list?

Simplicity Respondents had many different criteria for greatness in equations. Half a dozen people were so impressed with simplicity that they proposed 1 + 1 = 2. “I know that other equations have done more, express greater power [and have … Continue reading

## Magic Squares

In a magic square you have to add 3 numbers again and again the average sum of three numbers is 45/3 = 15 15 is called the magic number of the 3×3 square All the eight squares change into each … Continue reading

Posted in Number Puzzles, Uncategorized | Tagged | 1 Comment

## Permutations of Numbers

4356 = (1.5) * 6534 = (3/2) * 6534 85427136 = 2 * 42713568 = 4 * 21356784 = 6 * 14237856 using 3 permutations of the number itself (no digit 9 in all numbers) 142857 * 2 = 285714 … Continue reading

## Pandigital numbers: numbers containing the digits 0-9

1023456789, 1023456798, 1023456879, 1023456897, 1023456978, 1023456987, 1023457689, 1023457698, 1023457869, 1023457896, 1023457968, 1023457986, 1023458679, 1023458697, 1023458769, 1023458796, 1023458967, 1023458976 Table of n, a(n) for n = 1, .. ,1000 https://oeis.org/A050278/b050278.txt A = Pandigital numbers B = 2 * (a zero-less pandigital … Continue reading

## Using all digits only once to make the num3er 9

(1) Ratios that use each of 9 digits 1-9 once 57429 ————- = 9 6381 58239 ————- = 9 6471 75249 ————- = 9 8361 (2) Ratios that use each of 10 digits 0-9 once 97524 ————- = 9 10836 … Continue reading

## Using digits 1 to 9 only once to make the num3er 8

See also: Using all digits from 1 to 9 only once to make 2 (Part 4) Using all digits from 0 to 9 only once (Part 3) Using all digits 0 to 9 only once to make a sum equal … Continue reading

## Using digits 1 to 9 only once to make 3, 4, 5, 6, 7

17469 ————– = 3 5823 17496 ————– = 3 5832 15768 ————– = 4 3942 17568 ————– = 4 4392 23184 ————– = 4 5796 31824 ————– = 4 7956 13485 ————— = 5 2697 13845 —————- = 5 2769 … Continue reading