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A279205 Length of second run of 1's in binary representation of Catalan(n). 2
0, 0, 0, 1, 0, 1, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 3, 4, 1, 3, 2, 1, 6, 1, 2, 1, 4, 7, 5, 2, 3, 1, 4, 2, 1, 1, 5, 2, 1, 3, 1, 1, 3, 3, 3, 3, 8, 2, 1, 2, 2, 1, 3, 2, 2, 1, 1, 1, 1, 3, 2, 1, 1, 2, 1, 4, 1, 2, 4, 1, 2, 3, 1, 1, 1, 2, 1, 1, 5, 1, 1, 1, 5, 4, 3, 2, 2, 2, 1, 1, 1, 1, 1, 1, 3, 2, 2, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,9
COMMENTS
Suggested by A279026.
What combinatorial problem is this the answer to?
LINKS
EXAMPLE
A000108(13) = 742900_10 = A264663(13) = 10110101010111110100_2, so a(13) = 2.
MATHEMATICA
Q = {};
Num = 100;
T = Table[IntegerDigits[CatalanNumber[n], 2], {n, 0, Num}];
For[i = 1, i <= Num, i++,
c = 0; j = 1;
While[T[[i]][[j]] == 1, j++];
While[T[[i]][[j]] == 0, j++];
c = j;
While[T[[i]][[j]] == 1, j++];
c = j - c;
AppendTo[Q, c]
];
Q (* Benedict W. J. Irwin, Dec 21 2016 *)
Join[{0, 0, 0, 1, 0}, Length[Split[IntegerDigits[#, 2]][[3]]]&/@ CatalanNumber[ Range[5, 100]]] (* Harvey P. Dale, Aug 20 2021 *)
CROSSREFS
Sequence in context: A022300 A347552 A300983 * A105690 A214364 A175922
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Dec 21 2016
EXTENSIONS
a(19) to a(99) from Benedict W. J. Irwin, Dec 21 2016
STATUS
approved

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Last modified July 22 00:58 EDT 2024. Contains 374478 sequences. (Running on oeis4.)