challenge - prime numbers where sum of squared digits of prime number is also prime

[TheKaneB]

Yup, the "happy number" refers to an entire sequence:

Quote:For example, 19 is happy, as the associated sequence is:

1^2 + 9^2 = 82
8^2 + 2^2 = 68
6^2 + 8^2 = 100
1^2 + 0^2 + 0^2 = 1.

At the end of the sequence you must meet the number 1 (one). So it's related to, but different from, the question from the OP