A067205 Least numbers with n = digital root = number of prime factors.

19, 38, 12, 40, 32, 96, 448, 1664, 1152

Offset

1,1

Comments

For 1 <= n <= 9: A010888(a(n)) = A001222(a(n)) = n.

Links

Table of n, a(n) for n=1..9.

Example

a(7)=448 as A001222(448)=7 because of 448=2*2*2*2*2*2*7
and A010888(448)=7 because of 4+4+8=16 and 1+6=7.

Crossrefs

Cf. A007953.

Sequence in context: A144594 A287310 A123028 * A196185 A040342 A164009

Adjacent sequences: A067202 A067203 A067204 * A067206 A067207 A067208

Keyword

nonn,base,fini,full

Author

Reinhard Zumkeller, Feb 19 2002

Status

approved