An isolated prime is a prime number p such that neither p − 2 nor p + 2 is prime. In other words, p is not part of a twin prime pair. For example, 23 is an isolated prime since 21 and 25 are both composite.
The first few isolated primes are
- 2, 23, 37, 47, 53, 67, 79, 83, 89, 97, … (sequence A007510 in OEIS).
Read more about this topic: Twin Prime
Famous quotes containing the words isolated and/or prime:
“I can’t earn my own living. I could never make anything turn into money. It’s like making fires. A careful assortment of paper, shavings, faggots and kindling nicely tipped with pitch will never light for me. I have never been present when a cigarette butt, extinct, thrown into a damp and isolated spot, started a conflagration in the California woods.”
—Margaret Anderson (1886–1973)
“Faith in reason as a prime motor is no longer the criterion of the sound mind, any more than faith in the Bible is the criterion of righteous intention.”
—George Bernard Shaw (1856–1950)