%I A072037
%S A072037 4,8,9,121,343,1331,10201,14641,94249,1030301,104060401,
%T A072037 900075181570009,10022212521222001,12124434743442121,12323244744232321,
%U A072037 12341234943214321
%N A072037 Palindromic powers of a prime but not a prime (A025475).
%e A072037 E.g. 94249=307*307
%t A072037 a = {}; Do[pp = Prime[n]^i; d = IntegerDigits[pp]; If[d == Reverse[d],
a = Append[a, pp]], {n, 1, PrimePi[ Sqrt[10^21]]}, {i, 2, Floor[
Log[ Prime[n], 10^21]]}]; Sort[a] (Robert G. Wilson v)
%o A072037 (PARI) {a=10^15; v=[]; m=sqrt(a); forprime(p=2,m,q=p; while((q=q*p)<a,
n=q; rev=0; while(n>0,d=divrem(n,10); n=d[1]; rev=10*rev+d[2]); if(q==rev,
v=concat(v,q)))); v=vecsort(v); for(j=1,matsize(v)[2],print1(v[j],
","))}
%Y A072037 Cf. A025475, A002385.
%Y A072037 Sequence in context: A075786 A046450 A077271 this_sequence A084093 A076703
A141220
%Y A072037 Adjacent sequences: A072034 A072035 A072036 this_sequence A072038 A072039
A072040
%K A072037 base,easy,nonn
%O A072037 1,1
%A A072037 Labos E. (labos(AT)ana.sote.hu), Jun 07 2002
%E A072037 Two more term from Klaus Brockhaus (klaus-brockhaus(AT)t-online.de),
Jun 07 2002
%E A072037 Four more terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Oct 31 2002
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