A089369 Begin with n and place (n-1) on the least significant side, place (n-2) on the most significant side and so on until a 1 is placed.

1, 21, 132, 2431, 13542, 246531, 1357642, 24687531, 135798642, 24681097531, 1357911108642, 246810121197531, 13579111312108642, 2468101214131197531, 135791113151412108642, 24681012141615131197531

Offset

1,2

Links

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

Example

a(6)= 246531, the steps are 6 -> 65 -> 465 -> 4653 -> 24653 -> 246531.

Mathematica

f[n_] := Block[{j = 1, k = n - 1, d = IntegerDigits[n]}, While[k > 0, If[ EvenQ[j], d = Join[ IntegerDigits[k], d], d = Join[d, IntegerDigits[k]]]; j++; k-- ]; FromDigits[d]]; Table[ f[n], {n, 17}]

Crossrefs

Cf. A089370.

Sequence in context: A008384 A110400 A308348 * A328861 A243201 A264554

Adjacent sequences: A089366 A089367 A089368 * A089370 A089371 A089372

Keyword

base,easy,nonn

Author

Amarnath Murthy, Nov 08 2003

Extensions

More terms from Robert G. Wilson v, Nov 08 2003

Status

approved