A100373 Lexicographically earliest increasing sequence of composite numbers such that the digits of a(n) do not appear in a(n-1).

4, 6, 8, 9, 10, 22, 30, 42, 50, 62, 70, 81, 90, 111, 200, 314, 500, 611, 700, 812, 900, 1111, 2000, 3111, 4000, 5111, 6000, 7111, 8000, 9111, 20000, 31111, 40000, 51111, 60000, 71111, 80000, 91111, 200000, 311113, 400000, 511112, 600000, 711111

Offset

1,1

Links

Table of n, a(n) for n=1..44.

Mathematica

ta={1}; Do[s1=IntegerDigits[Part[ta, Length[ta]]]; s2=IntegerDigits[n]; If[Equal[Intersection[s1, s2], {}] &&!PrimeQ[n], Print[{Last[ta], n}]; ta=Append[ta, n]], {n, 1, 1000000}]; ta=Delete[ta, 1]

Crossrefs

Cf. A002808, A030283-A030290.

Sequence in context: A372308 A320726 A205530 * A211302 A123938 A121150

Adjacent sequences: A100370 A100371 A100372 * A100374 A100375 A100376

Keyword

base,nonn

Author

Labos Elemer, Dec 01 2004

Status

approved