A112717 9-digit numbers n such that phi(n) = d_1 d_2 d_3*d_4 d_5 d_6* d_7 d_8 d_9 where d_1 d_2 ... d_9 is the decimal expansion of n.

102873384, 104754444, 104840625, 104963320, 106600792, 108512770, 108860625, 108864585, 110640784, 110756648, 116660400, 116672500, 117480648, 120297912, 120876448, 120916400, 121864290, 124704384, 125792500, 126528640, 128333700

Offset

1,1

Links

Table of n, a(n) for n=1..21.

Example

phi(128972250)=128*972*250, so 128972250 is in the sequence.

Mathematica

Do[h=IntegerDigits[n]; k=Length[h]; If[EulerPhi[n]==Product[ 100*h[[3j-2]]+10h[[3j-1]]+h[[3j]], {j, k/3}], Print[n]], {n, 10^8, 128400000}]

Crossrefs

Cf. A058627, A112714, A112715.

Sequence in context: A235161 A235724 A241792 * A114679 A157859 A157863

Adjacent sequences: A112714 A112715 A112716 * A112718 A112719 A112720

Keyword

base,fini,nonn

Author

Farideh Firoozbakht, Sep 16 2005

Status

approved