A097644 Numbers n such that pi(n) = reversal(n).

51, 130, 370, 8201, 73270, 82080, 26113610, 4854248220, 37682961610

Offset: 1

Author

Farideh Firoozbakht, Aug 25 2004

Keywords

• base
• nonn

Comments

This sequence has only two odd terms, i.e., 51 and 8201 and 10 divides all other terms. Next term is greater than 10^8.

Examples

			26113610 is in the sequence because
pi(26113610) = 1631162 = reversal(26113610).
		

Crossrefs

Cf. A037171, A069215.

Programs

Mathematica

Do[If[PrimePi[m]==FromDigits[Reverse[IntegerDigits[m]]], Print[m]], {m, 100000000}]

Extensions

Two more terms from Giovanni Resta, Feb 06 2006