A059004 Smallest prime whose reversal is an n-th power.

2, 61, 521, 61, 23, 61277761, 821, 61277761, 23888027348153, 4201, 33670369817243, 61277761, 5265674839116110941, 441435249928911950281, 23888027348153, 1232787935486158110509626783, 270131

Offset: 1

Author

Robert G. Wilson v, Jan 16 2001

Keywords

• nonn
• base

Links

• Robert Israel, Table of n, a(n) for n = 1..271

Crossrefs

Cf. A007488.

Programs

Maple

revdigs:= proc(n) local L,k;
  L:= convert(n,base,10);
  add(L[-k]*10^(k-1),k=1..nops(L))
end proc:
f:= proc(n) local d, k, wmin,  v,w;
  wmin:= infinity;
  for d from 1 do
    for k from ceil(10^(d/n)) do
      v:= k^n;
      if v >= 10^(d+1) then break fi;
      w:= revdigs(v);
      if isprime(w) and w < wmin then wmin:= w fi;
    od;
    if wmin < infinity then return wmin fi
  od
end proc:
map(f, [$1..20]); # Robert Israel, May 22 2019

Mathematica

Do[ k = 1; While[ r = ToExpression[ StringReverse[ ToString[ k^n ] ] ]; ! PrimeQ[ r ], k++ ]; Print[ r ], {n, 1, 25} ]