A105268 Primes which are 1 + strobogrammatic numbers A000787(n): the same upside down.

2, 89, 97, 809, 907, 8009, 8699, 9697, 9887, 81119, 98887, 8000009, 9888887, 81111119, 8111111119, 8666699999, 9888888887, 8000000000009, 9888888888887, 98888888888888887, 81111111111111111119, 800000000000000000009

Offset: 1

Author

Jonathan Vos Post, Apr 16 2005

Keywords

• base
• easy
• nonn

Comments

Primes which, upon subtracting one, give numbers which read the same upside-down. Not to be confused with strobogrammatic primes A007597 such as 181 or 619. Also, 263 is the largest known prime whose square is strobogrammatic. Not to be confused with strobogrammatic squares A018848 such as 109181601. After a(7) this sequence is exemplary, not complete (i.e. missing some values).

Examples

			9887 is prime, 9887 = 9886+1 and 9886 turned upside-down is 9886 again.
		

Crossrefs

Cf. A000040, A000787, A007597, A018847, A018848.

Formula

{A000787(n)+1} intersect {A000040}.

Extensions

Term a(17) reordered by Georg Fischer, Mar 20 2022