A173716 Smallest number that contains the first n semiprimes as substrings.

4, 46, 469, 10469, 101469, 10141569, 101421569, 1014221569, 101421522569, 1014215225269, 101421522526339, 1014215225263349, 101421522526334359, 10142152252633435389, 101421522526334353839, 1014215225263346353839

Offset

1,1

Comments

Semiprime analog of A054261.

References

Jonathan Vos Post, Posting to the Sequence Fans Mailing List, May 24 2010

Links

Table of n, a(n) for n=1..16.

Crossrefs

Cf. A000040, A001358, A054260, A035239, A178057, A144565, A169798.

Sequence in context: A194488 A132932 A231787 * A320229 A097952 A097643

Adjacent sequences: A173713 A173714 A173715 * A173717 A173718 A173719

Keyword

nonn,base,more

Author

N. J. A. Sloane, Nov 25 2010

Extensions

More terms from Sean A. Irvine, Dec 02 2010

Status

approved