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A115894
Numbers k such that phi(k)*prime(k) is a palindrome.
1
1, 2, 5, 16, 534, 7412, 17280, 146533, 633932, 1424705, 5879645
OFFSET
1,2
EXAMPLE
phi(17280)*prime(17280) = 4608*191461 = 882252288.
MATHEMATICA
pppQ[n_]:=Module[{c=IntegerDigits[EulerPhi[n]Prime[n]]}, c == Reverse[c]]; Select[Range[6000000], pppQ] (* Harvey P. Dale, Aug 01 2012 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Feb 06 2006
STATUS
approved