A004428 Geometric mean of digits of n (rounded down).

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 1, 1, 2, 2, 2, 2, 2, 3, 0, 1, 2, 2, 2, 3, 3, 3, 4, 4, 0, 1, 2, 3, 3, 3, 4, 4, 4, 5, 0, 2, 2, 3, 4, 4, 4, 5, 5, 6, 0, 2, 3, 3, 4, 5, 5, 5, 6, 6, 0, 2, 3, 4, 4, 5, 6, 6, 6, 7, 0, 2, 3, 4, 5, 5, 6, 7, 7, 7, 0, 2, 4, 4, 5, 6, 6, 7, 8, 8, 0, 3, 4, 5, 6, 6, 7, 7, 8, 9, 0, 0, 0, 0, 0, 0, 0, 0

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• base

Comments

a(n) = 0 for almost all n (in the sense of asymptotic density). - Charles R Greathouse IV, Jan 30 2023

Crossrefs

Cf. A004429, A007954, A257830.

Programs

Mathematica

A004428[n_] := Floor[GeometricMean[IntegerDigits[n]]]

PARI

A004428(n)=sqrtn(prod(i=1,#n=digits(n),n[i]),#n)\1 \\ M. F. Hasler, May 10 2015