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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

Table of n, a(n) for n=0..89.

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

Adjacent sequences:  A052170 A052171 A052172 * A052174 A052175 A052176

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 March 28 11:00 EDT 2020. Contains 333083 sequences. (Running on oeis4.)