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A122950 Triangle T(n,k), 0<=k<=n, read by rows, given by [0, 0, 1, -1, 0, 0, 0, 0, 0, 0, ...] DELTA [1, 1, -1, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938. 18
1, 0, 1, 0, 0, 2, 0, 0, 1, 3, 0, 0, 0, 3, 5, 0, 0, 0, 1, 7, 8, 0, 0, 0, 0, 4, 15, 13, 0, 0, 0, 0, 1, 12, 30, 21, 0, 0, 0, 0, 0, 5, 31, 58, 34, 0, 0, 0, 0, 0, 1, 18, 73, 109, 55, 0, 0, 0, 0, 0, 0, 6, 54, 162, 201, 89, 0, 0, 0, 0, 0, 0, 1, 25, 145, 344, 365, 144, 0, 0, 0, 0, 0, 0, 0, 7, 85, 361, 707 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,6

COMMENTS

Skew triangle associated with the Fibonacci numbers.

LINKS

Table of n, a(n) for n=0..88.

FORMULA

Sum_{k, 0<=k<=n}T(n,k)=A011782(n) . Sum_{n,n>=k}T(n,k)=A001333(k) . T(n,k)=0 if k<0 or if k>n, T(0,0)=1, T(2,1)=0, T(n,k)=T(n-1,k-1)+T(n-2,k-1)+T(n-2,k-2) . T(n,n)=Fibonacci(n+1)=A000045(n+1).

Sum_{k, 0<=k<=n}T(n,k)*x^k = A000007(n), A011782(n), A133592(n), A133594(n), A133642(n), A133646(n), A133678(n), A133679(n), A133680(n), A133681(n) for x = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 respectively . - Philippe DELEHAM, Jan 03 2008

G.f.: (1-y*x^2)/(1-y*x-y*(y+1)*x^2). - From Philippe Deléham, Nov 26 2011

EXAMPLE

Triangle begins:

.1;

.0, 1;

.0, 0, 2;

.0, 0, 1, 3;

.0, 0, 0, 3, 5;

.0, 0, 0, 1, 7, 8;

.0, 0, 0, 0, 4, 15, 13;

.0, 0, 0, 0, 1, 12, 30, 21;

.0, 0, 0, 0, 0, 5, 31, 58, 34;

.0, 0, 0, 0, 0, 1, 18, 73, 109, 55;

.0, 0, 0, 0, 0, 0, 6, 54, 162, 201, 89;

.0, 0, 0, 0, 0, 0, 1, 25, 145, 344, 365, 144;

.0, 0, 0, 0, 0, 0, 0, 7, 85, 361, 707, 655, 233;

CROSSREFS

Cf. A055830 (another version).

Sequence in context: A051510 A153036 A182114 * A116489 A166373 A202451

Adjacent sequences:  A122947 A122948 A122949 * A122951 A122952 A122953

KEYWORD

nonn,tabl

AUTHOR

Philippe DELEHAM, Oct 25 2006

STATUS

approved

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Last modified June 18 03:02 EDT 2013. Contains 226328 sequences.