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A069969 Numbers n such that phi(reverse(n)) = phi(reverse(n-1)) + phi(reverse(n-2)). 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
phi(reverse(223)) = phi(322) = 132 = 72 + 60 = phi(222) + phi(122) = phi(reverse(223-1)) + phi(reverse(223-2)).
MATHEMATICA
rev[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Select[Range[3, 10^5], EulerPhi[rev[ # ]] == EulerPhi[rev[ # - 1]] + EulerPhi[rev[ # - 2]] &]
CROSSREFS
Sequence in context: A095714 A137864 A256154 * A067232 A327413 A106115
KEYWORD
base,nonn
AUTHOR
Joseph L. Pe, Apr 29 2002
STATUS
approved

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Last modified March 29 00:26 EDT 2024. Contains 371264 sequences. (Running on oeis4.)