A108203 Numbers n put into lexicographical order which are the concatenation of k and the sum of the digits of k.

11, 22, 33, 44, 55, 66, 77, 88, 99, 101, 112, 123, 134, 145, 156, 167, 178, 189, 202, 213, 224, 235, 246, 257, 268, 279, 303, 314, 325, 336, 347, 358, 369, 404, 415, 426, 437, 448, 459, 505, 516, 527, 538, 549, 606, 617, 628, 639, 707, 718, 729, 808, 819, 909, 1001

Offset

1,1

Links

Table of n, a(n) for n=1..55.

Example

1 --> 11, 2 --> 22, 3 --> 33, ..., 9 --> 99, 10 --> 101, 11 --> 112, 12 --> 123,
..., 18 --> 189, 19 --> 1910 (ouch!), 20 --> 202, 21 --> 213, ...

Mathematica

f[n_] := FromDigits[ Join[ IntegerDigits[ n], IntegerDigits[Plus @@ IntegerDigits[ n]] ]]; t = {}; Do[t = Union[AppendTo[t, f[n]]], {n, 10^6}]

Crossrefs

Cf. A062028, A064806. Equals A108773 sorted.

Sequence in context: A343444 A193772 A178359 * A308104 A108773 A282151

Adjacent sequences: A108200 A108201 A108202 * A108204 A108205 A108206

Keyword

base,nonn

Author

Eric Angelini and Robert G. Wilson v, Jun 15 2005

Extensions

a(55) from Rémy Sigrist, May 16 2019

Status

approved