What are the next two numbers in this sequence?
1, 1, 7, 3, 23, 23, 111, 15, 351, 415, __, __

1. All numbers are odd.

2. Adding adjacent pairs provides the following sequence:
2, 8, 10, 26, 46, 134, 366, 766  (I have no idea what that means...)

3. The first 6 are primes.

4. The next 4 are multiples of 3.

5. When looking at the list in groups of 4, the first two in the group are the same or similar size, the third is much larger than the first two, and the 4th is much smaller than the 3rd.

 

I imagine the next number in the list to be in the range of 1000-3000, and the last number in the list to be in the range of 100-500.

Hmmm, Roman numerals...
I
I
VII
III
XXIII
XXIII
CXI
XV
CCCLI
CLXV
.
.
.

MCL = 1150
CV = 105

Posted by Erik on 2004-06-02 16:12:50