A068671 Define f(n,k) = floor[n/k] and a(n) = right concatenation of f(n,k) for k = 1 to int[(n+1)/2] or until one arrives at a 1.

1, 21, 31, 421, 521, 6321, 7321, 84221, 94321, 1053221, 1153221, 12643221, 13643221, 147432221, 157533221, 1685432221, 1785432221, 18964332221, 19964332221, 2010654322221, 2110754332221, 22117543322221, 23117543322221

Offset

1,2

Links

Table of n, a(n) for n=1..23.

Example

a(13) = 13643221. as int[13/6] =2, floor[13/7] = 1 hence floor [13/8]=1 etc. are not used in the concatenation.

Crossrefs

Sequence in context: A176558 A243360 A068657 * A166668 A019423 A002639

Adjacent sequences: A068668 A068669 A068670 * A068672 A068673 A068674

Keyword

base,easy,nonn

Author

Amarnath Murthy, Mar 02 2002

Status

approved