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A123594
Unique sequence of 0's and 1's which are either repeated or not repeated with the following property: when the sequence is 'coded' in writing down a 1 when an element is repeated and a 0 when it is not repeated and by putting the initial element in front of the sequence thus obtained, the above sequence appears.
2
1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0
OFFSET
1,1
LINKS
Vantieghem Emmanuel, Nov 14 2006, Table of n, a(n) for n = 1..620
FORMULA
a(n+2) = A000002(n)-1. - Danny Rorabaugh, Mar 04 2015
MATHEMATICA
a = {1, 1, 0}; i = 2; Label[be]; i += 1; t = Part[a, i]; If[t == 0, b = {a, 1 - Part[a, Length[a]]}; a := Flatten[b], b = {a, Part[a, Length[a]]}; a := Flatten[b]; b = {a, 1 - Part[a, Length[a]]}; a := Flatten[b]]; If[i > 1000, Print[a], Goto[be]]
CROSSREFS
Cf. A000002.
Sequence in context: A353816 A141727 A298952 * A286801 A189091 A344863
KEYWORD
easy,nonn
AUTHOR
Emmanuel Vantieghem, Nov 14 2006
STATUS
approved