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A052173 Another version of the Catalan triangle A008315. 1
1, 1, 0, 1, 0, 1, 1, 0, 2, 0, 1, 0, 3, 0, 2, 1, 0, 4, 0, 5, 0, 1, 0, 5, 0, 9, 0, 5, 1, 0, 6, 0, 14, 0, 14, 0, 1, 0, 7, 0, 20, 0, 28, 0, 14, 1, 0, 8, 0, 27, 0, 48, 0, 42, 0, 1, 0, 9, 0, 35, 0, 75, 0, 90, 0, 42, 1, 0, 10, 0, 44, 0, 110, 0, 165, 0, 132, 0, 1, 0, 11, 0, 54, 0, 154, 0, 275, 0, 297, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,9
LINKS
R. K. Guy, Catwalks, sandsteps and Pascal pyramids, J. Integer Sequences, Vol. 3 (2000), Article #00.1.6
W. F. Klostermeyer, M. E. Mays, L. Soltes and G. Trapp, A Pascal rhombus, Fibonacci Quarterly, 35 (1997), 318-328.
FORMULA
a(n, k) = a(n-1, k-2)+a(n-1, k) with a(0, 0)=1 and a(n, k)=0 if k < 0 or k > n.
EXAMPLE
1;
1 0;
1 0 1;
1 0 2 0;
1 0 3 0 2;
1 0 4 0 5 0;
1 0 5 0 9 0 5;
...
CROSSREFS
See A008315 (the main entry for this triangle) for more information.
Reflection of A053121.
Sequence in context: A104477 A224928 A308066 * A177825 A175790 A124305
KEYWORD
nonn,easy,tabl
AUTHOR
N. J. A. Sloane, Jan 26 2000
EXTENSIONS
More terms from Henry Bottomley, Aug 23 2001
STATUS
approved

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Last modified July 18 21:02 EDT 2024. Contains 374388 sequences. (Running on oeis4.)