A101697 Numbers n such that phi(n) is equal to d_1!+d_2!+...+d_k!, where d_1 d_2 ... d_k is the decimal expansion of n.

1, 67585, 84466, 854696

Offset

1,2

Links

Table of n, a(n) for n=1..4.

Shyam Sunder Gupta, Fascinating Factorials, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 16, 411-442.

Example

854696 is in the sequence because phi(854696)=8!+5!+4!+6!+9!+6!.

Mathematica

Do[h = IntegerDigits[n]; l = Length[h]; If[EulerPhi[n] == Sum[h[[k]]!, {k, l}], Print[n]], {n, 10000000}]

Crossrefs

Cf. A100416.

Sequence in context: A198537 A249208 A234120 * A247221 A224655 A234655

Adjacent sequences: A101694 A101695 A101696 * A101698 A101699 A101700

Keyword

base,fini,full,nonn

Author

Farideh Firoozbakht, Dec 12 2004

Status

approved