A022499 Describe the previous term! (method B - initial term is 3).

3, 31, 3111, 3113, 311231, 3112213111, 311222113113, 31122312311231, 3112223111213112213111, 31122331132111311222113113, 311222321231211331122312311231

Offset

1,1

Comments

Method B = 'digit'-indication followed by 'frequency'.

Links

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

Example

E.g. the term after 3113 is obtained by saying "3 once, 1 twice, 3 once", which gives 311231.

Mathematica

a[1] = 3;
a[n_] := a[n] = {#[[1]], Length[#]}& /@ Split[a[n-1] // IntegerDigits] // Flatten // FromDigits;
Array[a, 11] (* Jean-François Alcover, Jul 13 2016, updated Jan 05 2018 *)

Crossrefs

Cf. A007651, A022470, A022500-A022505.

Cf. A006715.

Sequence in context: A172645 A201604 A048562 * A129209 A134721 A002707

Adjacent sequences: A022496 A022497 A022498 * A022500 A022501 A022502

Keyword

nonn,base,easy,nice

Author

N. J. A. Sloane

Status

approved