A048527 Primes for which only five iterations of 'Prime plus its digit sum equals a prime' are possible.

516493, 1056493, 1427383, 1885943, 3166183, 3805183, 4241593, 6621283, 7646953, 12912283, 17987839, 32106493, 107152093, 120224773, 131144473, 133210873, 139388891, 142782877, 150326173, 155382923, 177865819, 184081943, 227795839, 242376877, 264174877

Offset: 1

Author

Patrick De Geest, May 15 1999

Keywords

• nonn
• base

Examples

			516493 -> 516521 -> 516541 -> 516563 -> 516589 -> 516623 -> next iteration yields a composite.
		

Links

• Lars Blomberg, Table of n, a(n) for n = 1..3000

Crossrefs

Cf. A047791, A048519, A062028 (n + digit sum of n).

Cf. A048523, A048524, A048525, A048526.

Programs

PARI

forprime(p=2,,isprime(pp=A062028(p))&& !for(i=2,5,isprime(pp=A062028(pp))||next(2))&& !isprime(A062028(pp))&& print1(p",")) \\ M. F. Hasler, Nov 08 2018

Extensions

Offset changed to 1 and a(15)-a(24) from Lars Blomberg, Dec 04 2013