A090103 n written in base equal to the number of distinct prime factors of n and a(1)=0.

0, 11, 111, 1111, 11111, 110, 1111111, 11111111, 111111111, 1010, 11111111111, 1100, 1111111111111, 1110, 1111, 1111111111111111, 11111111111111111, 10010, 1111111111111111111, 10100, 10101, 10110, 11111111111111111111111, 11000

Offset

1,2

Comments

All primes p are written in number-system of base one so rather long strings of 11...111 arise.

Links

Table of n, a(n) for n=1..24.

Formula

n in base A001221(n).

Example

a(6469693230) = 6469693230.
Symbol A to denote "10" first appears at n = 200560490130 = A002110(11).

Mathematica

tn[x_] := Fold[nd, 0, x]; Do[s=lf[n]; If[Equal[s, 1], Print[tn[Table[1, {i, 1, n}]]]]; If[ !Equal[s, 1], Print[tn[IntegerDigits[n, s]]]], {n, 2, 211}]

Crossrefs

Cf. A002110, A001221, A031974 (primes in base one).

Sequence in context: A284419 A283849 A283604 * A061851 A247552 A138145

Adjacent sequences: A090100 A090101 A090102 * A090104 A090105 A090106

Keyword

base,nonn

Author

Labos Elemer, Dec 16 2003

Status

approved