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

1,1

Links

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

Example

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

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 *)

Prog

(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

Crossrefs

Cf. A025475, A007488, A069798.

Sequence in context: A141870 A115685 A069798 * A355984 A355985 A232235

Adjacent sequences: A067191 A067192 A067193 * A067195 A067196 A067197

Keyword

nonn,base

Author

Shyam Sunder Gupta, Feb 19 2002

Extensions

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

Status

approved