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%I #9 Jul 15 2021 21:23:39
%S 1,2,5,16,534,7412,17280,146533,633932,1424705,5879645
%N Numbers k such that phi(k)*prime(k) is a palindrome.
%e phi(17280)*prime(17280) = 4608*191461 = 882252288.
%t pppQ[n_]:=Module[{c=IntegerDigits[EulerPhi[n]Prime[n]]},c == Reverse[c]]; Select[Range[6000000],pppQ] (* _Harvey P. Dale_, Aug 01 2012 *)
%Y Cf. A084122, A115891, A115893.
%K nonn,base
%O 1,2
%A _Giovanni Resta_, Feb 06 2006
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