Wednesday, September 26

1051 & 1061

1051 is the 177th prime and 1061 is the 178th. We can create palindromes out of the two numbers in three easy ways:

1051 + 1061 = 2112

1051 * 1061 = 1115111

1051^2 + 1061^2 = 2230322

Monday, September 10

A prime number of consecutive primes summing to a repdigit prime

I suppose that 2 + 3 = 5 is an example, even though the 5 is a degenerate repdigit number. A more proper solution is 158730158730158647 + 158730158730158681 + 158730158730158699 + 158730158730158723 + 158730158730158759 + 158730158730158783 + 158730158730158819 = 1111111111111111111, that sum being one of the few known repunit primes.

What else?