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A212126
Period 13: repeat (0,0,1,0,0,1,0,1,0,0,1,0,1).
0
0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1
OFFSET
0
COMMENTS
a(1)-a(42) coincide with A085242.
Consider the sequence in which a(n) = 1 if two rhombuses that are adjacent to one of the six spokes of the E-toothpick (or snowflake) structure of A161330 appear at n-th stage, otherwise 0. Is this the same as the mentioned sequence? If not, where is the first place these sequences differ? - Omar E. Pol, Feb 28 2013
FORMULA
G.f.: -x^2*(1 +x^3 +x^5 +x^8 +x^10) / ( (x-1)*(1 +x^12 +x^11 +x^10 +x^9 +x^8 +x^7 +x^6 +x^5 +x^4 +x^3 +x^2 +x) ). - R. J. Mathar, Mar 04 2013
MATHEMATICA
PadRight[{}, 120, {0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1}] (* Harvey P. Dale, Apr 13 2016 *)
PROG
(PARI) a(n)=[0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1][n%13+1] \\ Charles R Greathouse IV, Jul 17 2016
CROSSREFS
Very similar to but different from A189661. - N. J. A. Sloane, Mar 08 2017
Sequence in context: A289239 A188432 A282317 * A144605 A349297 A349317
KEYWORD
nonn,easy,changed
AUTHOR
Omar E. Pol, Dec 19 2012
STATUS
approved