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A162745
A Fibonacci-Pascal triangle.
1
1, 1, 1, 1, 3, 1, 1, 6, 6, 1, 1, 10, 20, 10, 1, 1, 15, 50, 50, 15, 1, 1, 21, 105, 173, 105, 21, 1, 1, 28, 196, 476, 476, 196, 28, 1, 1, 36, 336, 1120, 1643, 1120, 336, 36, 1, 1, 45, 540, 2352, 4707, 4707, 2352, 540, 45, 1, 1, 55, 825, 4530, 11775, 16040, 11775, 4530, 825, 55, 1
OFFSET
0,5
COMMENTS
Row sums are A162746.
LINKS
Paul Barry, On a Generalization of the Narayana Triangle, J. Int. Seq. 14 (2011) # 11.4.5.
FORMULA
T(n,k) = Sum_{j=0..n} C(n,j)*C(n-j,2(k-j))*Fibonacci(k-j+1).
EXAMPLE
Triangle begins
1;
1, 1;
1, 3, 1;
1, 6, 6, 1;
1, 10, 20, 10, 1;
1, 15, 50, 50, 15, 1;
1, 21, 105, 173, 105, 21, 1;
1, 28, 196, 476, 476, 196, 28, 1;
1, 36, 336, 1120, 1643, 1120, 336, 36, 1;
1, 45, 540, 2352, 4707, 4707, 2352, 540, 45, 1;
PROG
(PARI) T(n, k)=sum(j=0, n, binomial(n, j)*binomial(n-j, 2*(k-j))*fibonacci(k-j+1));
row(n) = vector(n+1, k, T(n, k-1)); \\ Michel Marcus, Nov 11 2022
CROSSREFS
Cf. A000045.
Sequence in context: A362242 A114176 A056241 * A001263 A162747 A107105
KEYWORD
easy,nonn,tabl
AUTHOR
Paul Barry, Jul 12 2009
STATUS
approved