|
| |
|
|
A001155
|
|
Describe the previous term! (method A - initial term is 0).
|
|
14
|
|
|
|
0, 10, 1110, 3110, 132110, 1113122110, 311311222110, 13211321322110, 1113122113121113222110, 31131122211311123113322110, 132113213221133112132123222110
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
COMMENTS
|
Method A = 'frequency' followed by 'digit'-indication.
|
|
|
REFERENCES
|
J. H. Conway, The weird and wonderful chemistry of audioactive decay, in T. M. Cover and Gopinath, eds., Open Problems in Communication and Computation, Springer, NY 1987, pp. 173-188.
S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 452-455.
I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood City, CA, 1991, p. 4.
|
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..20
S. R. Finch, Conway's Constant
|
|
|
EXAMPLE
|
E.g. the term after 3110 is obtained by saying "one 3, two 1's, one 0", which gives 132110.
|
|
|
MATHEMATICA
|
A001155[1] := 0; A001155[n_] := A001155[n] = FromDigits[Flatten[{Length[#], First[#]}&/@Split[IntegerDigits[A001155[n-1]]]]]; Map[A001155, Range[15]] (* Peter J. C. Moses, Mar 21 2013 *)
|
|
|
PROG
|
(PARI) A001155(n, a=0)={ while(n--, my(c=1); for(j=2, #a=Vec(Str(a)), if( a[j-1]==a[j], a[j-1]=""; c++, a[j-1]=Str(c, a[j-1]); c=1)); a[#a]=Str(c, a[#a]); a=concat(a)); a } \\ - M. F. Hasler, Jun 30 2011
|
|
|
CROSSREFS
|
Cf. A005150, A006751, A006715, A001140, A001141, A001143, A001145, A001151, A001154.
Cf. A036058.
Sequence in context: A204577 A210995 A036058 * A001391 A049064 A015026
Adjacent sequences: A001152 A001153 A001154 * A001156 A001157 A001158
|
|
|
KEYWORD
|
nonn,base,easy,nice
|
|
|
AUTHOR
|
N. J. A. Sloane.
|
|
|
STATUS
|
approved
|
| |
|
|
