A070028 Absolute primes: primes whose initial, all intermediate and final sums of digits are primes.

2, 3, 5, 7, 11, 113, 131, 311, 11111111111111111111111

Offset: 1

Author

Rick L. Shepherd, Apr 15 2002

Keywords

• base
• nonn

Comments

The next terms are R(317) and R(1031) where R(n)=(10^n-1)/9 is a repunit prime. This sequence is a subsequence of A003459 and A070027.

Examples

			113 is a term because 113 and permutations 131 and 311 are prime as is 1+1+3=5. 11111111111111111111111 is a term because it is prime, all permutations of its digits are prime, the sum of its digits, 23, is prime and 2+3=5 is also prime.
		

Crossrefs

Cf. A003459 (absolute primes), A004022 (repunit primes), A070027.