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A172414
Triangle read by rows: Catalan number C(n) repeated 2*n+1 times.
2
1, 1, 1, 1, 2, 2, 2, 2, 2, 5, 5, 5, 5, 5, 5, 5, 14, 14, 14, 14, 14, 14, 14, 14, 14, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 42, 132, 132, 132, 132, 132, 132, 132, 132, 132, 132, 132, 132, 132, 429, 429, 429, 429, 429, 429, 429, 429, 429, 429, 429, 429, 429, 429, 429
OFFSET
0,5
FORMULA
T(n,k) = A000108(n). - R. J. Mathar, Nov 03 2016
Sum_{n>=0} 1/a(n) = 6 + 44*Pi/(27*sqrt(3)). - Amiram Eldar, Aug 18 2022
EXAMPLE
Triangle begins:
......1
....1,1,1
..2,2,2,2,2
5,5,5,5,5,5,5,
MATHEMATICA
Table[PadRight[{}, 2*n + 1, CatalanNumber[n]], {n, 0, 8}] // Flatten (* Amiram Eldar, Aug 18 2022, after Harvey P. Dale at A172417 *)
CROSSREFS
Cf. A000108, A001700 (row sums), A172417, A168256.
Sequence in context: A215924 A115101 A241148 * A266995 A051887 A139516
KEYWORD
nonn,tabf,easy,less
AUTHOR
Mark Dols, Feb 02 2010
EXTENSIONS
Offset corrected by R. J. Mathar, Nov 03 2016
Data corrected and extended by Amiram Eldar, Aug 18 2022
STATUS
approved