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A121908 S-D transform of Catalan numbers A000108. +0
1
1, 2, 3, 9, 19, 72, 181 (list; graph; listen)
OFFSET

0,2

FORMULA

a(n) = Sum_{k, 0<=k<=n}A051159(n,k)*A000108(k).

EXAMPLE

1 1 2 5 14 42 132 ... (A000108)

2 1 7 9 56 90 ...

3 6 16 47 146 ...

9 10 63 99 ...

19 53 162 ...

72 109 ...

181 ...

Row 1 :A000108

Row 2 : 1+1=2, 2-1=1, 5+1=7, 14-5=9, 42+14=56, 132-42=90, ...

Row 3 : 1+2=3, 7-1=6, 9+7=16, 56-9=47, 90+56=146, ...

Row 4 : 6+3=9, 16-6=10, 47+16=63, 146-47=99, ...

Row 5 : 10+9=19, 63-10=53, 99+63=162, ...

Row 6 : 53+19=72, 162-53=109, ...

Row 7 ; 109+72=181, ...

First diagonal of this triangular array form this sequence.

CROSSREFS

Adjacent sequences: A121905 A121906 A121907 this_sequence A121909 A121910 A121911

Sequence in context: A079992 A106519 A006866 this_sequence A097075 A036673 A111189

KEYWORD

nonn

AUTHOR

Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 01 2006

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Last modified October 6 16:13 EDT 2008. Contains 144667 sequences.


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