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A139375 A Fibonacci-Catalan triangle. Also called the Fibonacci triangle. 6
1, 1, 1, 2, 2, 1, 3, 5, 3, 1, 5, 12, 9, 4, 1, 8, 31, 26, 14, 5, 1, 13, 85, 77, 46, 20, 6, 1, 21, 248, 235, 150, 73, 27, 7, 1, 34, 762, 741, 493, 258, 108, 35, 8, 1, 55, 2440, 2406, 1644, 903, 410, 152, 44, 9, 1, 89, 8064, 8009 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

First column is the Fibonacci numbers A000045(n+1). The second column is A090826.

Row sums are A090826(n+1). Diagonal sums are A139376. Inverse array is (1-x+2x^3-x^4,x(1-x)), A201167.

REFERENCES

He, Tian-Xiao, and Sprugnoli, Renzo; Sequence characterization of Riordan arrays. Discrete Math. 309 (2009), no. 12, 3962-3974. [From N. J. A. Sloane, Nov 26, 2011]

FORMULA

Riordan array (1/(1-x-x^2), xc(x)), c(x) the g.f. of A000108.

T(n,k)=k*sum(i=0..n-k,fibonacci(i+1)*binomial(2*(n-i)-k-1,n-i-1)/(n-i)) if k>0, and fibonacci(n+1) if k=0. [From Vladimir Kruchinin, Mar 09 2011]

EXAMPLE

Triangle begins

1,

1, 1,

2, 2, 1,

3, 5, 3, 1,

5, 12, 9, 4, 1,

8, 31, 26, 14, 5, 1,

13, 85, 77, 46, 20, 6, 1,

21, 248, 235, 150, 73, 27, 7, 1,

34, 762, 741, 493, 258, 108, 35, 8, 1

The production matrix for this array is

1, 1,

1, 1, 1,

-1, 1, 1, 1,

0, 1, 1, 1, 1,

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

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

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

CROSSREFS

Sequence in context: A106196 A037027 A182810 * A106198 A054336 A079956

Adjacent sequences:  A139372 A139373 A139374 * A139376 A139377 A139378

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Apr 15 2008

EXTENSIONS

Alternative name added by N. J. A. Sloane, Nov 27 2011

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Last modified February 16 05:39 EST 2012. Contains 205860 sequences.