Consider the sequence of dates given below:
$$6|12|71,2|1|72,29|1|72,25|2|72,\dots$$

What is the next term of the sequence?

Let us calculate the intervals in terms of days between consecutive terms in the sequence:
1. **From $6|12|71$ (6th Dec 1971) to $2|1|72$ (2nd Jan 1972):**
December has 31 days. Remaining days in Dec $=31-6=25$ days. Adding 2 days of January gives $25+2=27\text{days}$.
2. **From $2|1|72$ (2nd Jan 1972) to $29|1|72$ (29th Jan 1972):**
$29-2=27\text{days}$.
3. **From $29|1|72$ (29th Jan 1972) to $25|2|72$ (25th Feb 1972):**
January has 31 days. Remaining days in Jan $=31-29=2$ days. Adding 25 days of February gives $2+25=27\text{days}$.

The pattern shows a constant gap of exactly $27\text{days}$.
To find the next term, add $27\text{days}$ to $25|2|72$ (25th Feb 1972). Note that 1972 is a leap year, so February contains $29\text{days}$.

* Days remaining in February $=29-25=4$ days.
* Balance days to add in March $=27-4=23$ days.

Thus, the next date is 23rd March 1972, which translates to $23|3|72$.