The first digit is 2 That leaves digits 1,2,3,3,4,6,6,6 The first two digits then are 21, 22, 23, 24, or 26 If the first two digits are 21, the last digit is either 2,3,4, or 6 If the first two digits are 22, the last digit is either 1,3,4, or 6 If the first two digits are 23, the last digit is either 1,2,3,4, or 6 If the first two digits are 24, the last digit is either 1,2,3, or 6 If the first two digits are 26, the last digit is either 1,2,3,4, or 6 I count 22. That's not too many, so I'll just list them: 1. 212 2. 213 3. 214 4. 216 5. 221 6. 223 7. 224 8. 226 9. 231 10. 232 11. 233 12. 234 13. 236 14. 241 15. 242 16. 243 17. 246 18. 261 19. 262 20. 263 21. 264 22. 266 Edwin