Super-prime
Super-prime numbers, also known as higher-order primes or prime-indexed primes, are the subsequence of prime numbers that occupy prime-numbered positions within the sequence of all prime numbers. In other words, if prime numbers are matched with ordinal numbers, starting with prime number 2 matched with ordinal number 1, then the primes matched with prime ordinal numbers are the super-primes.
The subsequence begins
That is, if p denotes the nth prime number, the numbers in this sequence are those of the form p.
| n | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| p | 2 | 3 | 5 | 7 | 11 | 13 | 17 | 19 | 23 | 29 | 31 | 37 | 41 | 43 | 47 | 53 | 59 | 61 | 67 | 71 |
| p | 3 | 5 | 11 | 17 | 31 | 41 | 59 | 67 | 83 | 109 | 127 | 157 | 179 | 191 | 211 | 241 | 277 | 283 | 331 | 353 |
In 1975, Robert Dressler and Thomas Parker used a computer-aided proof to show that every integer greater than 96 may be represented as a sum of distinct super-prime numbers. Their proof relies on a result resembling Bertrand's postulate, stating that each super-prime number is less than twice its predecessor in the sequence.
A 2009 research showed that there are
super-primes up to x.
This can be used to show that the set of all super-primes is small.
One can also define "higher-order" primeness much the same way and obtain analogous sequences of primes.
A variation on this theme is the sequence of prime numbers with palindromic prime indices, beginning with