A224848 Reverse concatenation of the square of first a(n) integers gives a prime.

2, 3, 14, 700, 2818

Offset: 1

Author

Shyam Sunder Gupta, Jul 22 2013

Keywords

• nonn
• hard
• more
• base

Comments

The number corresponding to a(5) = 2818 is a probable prime of 18269 digits. - Giovanni Resta, Jul 25 2013

Examples

			a(4) = 700 because reverse concatenation of squares of 1 to 700 gives 490000488601......2516941 which is a 3742-digit prime number.
		

Crossrefs

Cf. A091314.

Extensions

a(5) from Giovanni Resta, Jul 25 2013