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A156062 Riordan array (1/(1-x^4), x/(1-x^4)). +0
2
1, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 2, 0, 0, 0, 1, 0, 0, 3, 0, 0, 0, 1, 0, 0, 0, 4, 0, 0, 0, 1, 1, 0, 0, 0, 5, 0, 0, 0, 1, 0, 3, 0, 0, 0, 6, 0, 0, 0, 1, 0, 0, 6, 0, 0, 0, 7, 0, 0, 0, 1, 0, 0, 0, 10, 0, 0, 0, 8, 0, 0, 0, 1, 1, 0, 0, 0, 15, 0, 0, 0, 9, 0, 0, 0, 1, 0, 4, 0, 0, 0, 21, 0, 0, 0, 10, 0, 0, 0 (list; table; graph; listen)
OFFSET

0,17

COMMENT

Row sums are A003269(n+1). Diagonal sums are the aerated Fibonacci numbers; thus

F(n+1)=sum{k=0..n, C((n+k)/2,k)*(1+(-1)^(n-k))/2}. Inverse is A156064.

FORMULA

Triangle T(n,k)=C((n+3k)/4,k)((1+(-1)^(n-k))/2+cos(pi*(n-k)/2))/2.

EXAMPLE

Triangle begins

1,

0, 1,

0, 0, 1,

0, 0, 0, 1,

1, 0, 0, 0, 1,

0, 2, 0, 0, 0, 1,

0, 0, 3, 0, 0, 0, 1,

0, 0, 0, 4, 0, 0, 0, 1,

1, 0, 0, 0, 5, 0, 0, 0, 1,

0, 3, 0, 0, 0, 6, 0, 0, 0, 1,

0, 0, 6, 0, 0, 0, 7, 0, 0, 0, 1,

0, 0, 0, 10, 0, 0, 0, 8, 0, 0, 0, 1,

1, 0, 0, 0, 15, 0, 0, 0, 9, 0, 0, 0, 1

Production matrix of this array is

0, 1,

0, 0, 1,

0, 0, 0, 1,

1, 0, 0, 0, 1,

0, 1, 0, 0, 0, 1,

0, 0, 1, 0, 0, 0, 1,

0, 0, 0, 1, 0, 0, 0, 1,

-3, 0, 0, 0, 1, 0, 0, 0, 1,

0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

0, 0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

15, 0, 0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

0, 15, 0, 0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

0, 0, 15, 0, 0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

0, 0, 0, 15, 0, 0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1,

-91, 0, 0, 0, 15, 0, 0, 0, -3, 0, 0, 0, 1, 0, 0, 0, 1

where 1,1,-3,15,-91,612,.... is (-1)^(n-1)*C(4n-1,n)/(4n-1) (see A006632).

CROSSREFS

Sequence in context: A127324 A083917 A117974 this_sequence A156064 A158757 A085983

Adjacent sequences: A156059 A156060 A156061 this_sequence A156063 A156064 A156065

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Oct 20 2009

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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


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