A113695 a(1) = 1, a(2) = 2 then the least number starting with n so that every term divides the concatenation of its neighbors.

1, 2, 30, 40, 520, 6120, 75080, 821920, 9125440, 1012882880, 11690270720, 127219466240, 1377297694720, 14982604718080, 1512710259671040, 16662943738757120, 178381140013219840, 18013061754595573760

Offset

1,2

Links

Table of n, a(n) for n=1..18.

Example

a(2)=2 divides the concatenated a(1)a(3)=130. a(3)=30 divides the concatenated a(2)a(4)=240. a(4)=40 divides the concatenated a(3)a(5)=30520.

Crossrefs

Cf. A113696.

Sequence in context: A343930 A127026 A105962 * A098827 A280380 A184238

Adjacent sequences: A113692 A113693 A113694 * A113696 A113697 A113698

Keyword

base,nonn

Author

Amarnath Murthy, Nov 11 2005

Extensions

Corrected and extended by R. J. Mathar, Aug 31 2007

Status

approved