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A067990 Triangle A067979 with rows read backwards. 10
1, 6, 3, 17, 13, 4, 38, 31, 19, 7, 80, 69, 48, 32, 11, 158, 140, 107, 79, 51, 18, 303, 274, 220, 176, 127, 83, 29, 566, 519, 432, 360, 283, 206, 134, 47, 1039, 963, 822, 706, 580, 459, 333, 217, 76, 1880, 1757, 1529 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

The column m (without leading 0's) gives the convolution of Lucas numbers {L(n+1) := A000204(n+1)}, n>=0, with those with m-shifted index: a(n+m,m)=sum(L(k+1)*L(m+n+1-k),k=0..n), n>=0,m=0,1,...

The columns give A004799(n-1), A067980-7 for m= 0..8, respectively. Row sums give A067989.

The row polynomials p(n,x) := sum(a(n,m)*x^m,m=0..n) are generated by A(z)*(A(z)-x*A(x*z))/(1-x), with A(x) := (1+2*x)/(1-x-x^2) (g.f. for Lucas {L(n+1)}).

FORMULA

a(n, m)=A067330(n, n-m), n>=m>=0, else 0.

a(n, m)=(n-m+1)*L(m+1)*F(n-m)+((n-m+1)*L(m+1)+(n-m)*L(m))*F(n-m+1), n>=m>=0, else 0; with F(n) := A000045(n)(Fibonacci) and L(n) := A000032(n) (Lucas).

G.f. for column m=0, 1, ...: (x^m)*(L(m+1)+L(m)*x)*(1+2*x)/(1-x-x^2)^2.

EXAMPLE

{1}; {6,3}; {17,13,4}; {38,31,19,7}; ...; p(2,x)=17+13*x+4*x^2.

CROSSREFS

Sequence in context: A097917 A116570 A046879 * A174012 A050008 A166450

Adjacent sequences:  A067987 A067988 A067989 * A067991 A067992 A067993

KEYWORD

nonn,easy,tabl

AUTHOR

Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), Feb 15 2002

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Last modified February 16 06:46 EST 2012. Contains 205867 sequences.