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A069969
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Numbers n such that phi(reverse(n)) = phi(reverse(n-1)) + phi(reverse(n-2)).
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0
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3, 5, 7, 34, 42, 83, 223, 342, 443, 464, 522, 563, 584, 653, 2194, 2554, 3623, 5704, 6904, 8084, 8134, 8254, 14455, 24653, 29393, 48023, 50882, 52834, 56663, 58483, 58814, 65893, 66784, 82315, 83324, 91373, 98254
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OFFSET
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1,1
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LINKS
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EXAMPLE
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phi(reverse(223)) = phi(322) = 132 = 72 + 60 = phi(222) + phi(122) = phi(reverse(223-1)) + phi(reverse(223-2)).
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MATHEMATICA
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rev[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Select[Range[3, 10^5], EulerPhi[rev[ # ]] == EulerPhi[rev[ # - 1]] + EulerPhi[rev[ # - 2]] &]
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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