A067194 Sequence of prime numbers whose reverse is a nontrivial prime power (A025475).

23, 61, 163, 521, 821, 1297, 1861, 4201, 9049, 9631, 12391, 14437, 16987, 92767, 94273, 96979, 108061, 123031, 125329, 127291, 142771, 148249, 165901, 180289, 270131, 906421, 906727, 906751, 921931, 942013, 942691, 965443, 969407, 986641

Offset: 1

Author

Shyam Sunder Gupta, Feb 19 2002

Keywords

• nonn
• base

Examples

			23 is a prime and its reversal is 32 = 2^5.
		

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..16435

Crossrefs

Cf. A025475, A007488, A069798.

Programs

Mathematica

a = {}; Do[ If[ PrimeQ[n], b = ToExpression[ StringReverse[ ToString[n]]]; If[ !PrimeQ[b] && Mod[b, b - EulerPhi[b]] == 0, a = Append[a, n]]], {n, 1, 10^6} ]; a
Select[Prime[Range[80000]],PrimePowerQ[IntegerReverse[#]]&& CompositeQ[ IntegerReverse[ #]]&] (* Harvey P. Dale, Dec 25 2021 *)

PARI

lista(nn) = {forprime(p=2, nn, if (ispower(subst(Polrev(digits(p)), x, 10),,&pp) && isprime(pp), print1(p, ", ")););} \\ Michel Marcus, Jun 03 2016

Extensions

Edited and extended by Robert G. Wilson v, Feb 19 2002 and Feb 24 2002