Thursday, April 19, 2007

Prime numbers ending in 67

Interesting prime number sequence: 67, 167, 367, 467, 967, 1367, 1567, 1667, 1867. Half the numbers ending in 67 before 1000 are prime. After that I just tested until 2067, and I found 4 more prime numbers ending in 67.
267 = 3 x 89
567 = 3 x 189 = 3^4 x 7
667 = 23 x 29
767 = 13 x 59
867 = 3 x 289 = 3 x 17 x 17
1067 = 11 x 97
1167 = 3 x 389
1267 = 7 x 181
1467 = 3 x 489 = 3 x 3 x 163
1767 = 3 x 19 x 31
1967 = 7 x 281
2067 = 3 x 13 x 53

2 comments:

Raila said...

Isso é MUITA falta do que fazer.

Unknown said...

Que nada! Faço isso enquanto estou à toa no ônibus!! Adoro fatorar placas de carro por exemplo! :P
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