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A125608 Triangle read by rows: given the left border = the Lucas numbers, (1, 3, 4, 7...), T(n,k) = (n-1,k) + (n-1,k-1). 1
1, 3, 1, 4, 4, 1, 7, 8, 5, 1, 11, 15, 13, 6, 1, 18, 26, 28, 19, 7, 1, 29, 44, 54, 47, 26, 8, 1, 47, 73, 98, 101, 73, 34, 9, 1, 76, 120, 171, 199, 174, 107, 43, 10, 1, 123, 196, 291, 370, 373, 281, 150, 53, 11, 1, 199, 319, 487, 661, 743, 654, 431, 203, 64, 12, 1, 322, 518, 806 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Row sums = A027973: (1, 4, 9, 21, 46, 99, 209...)

EXAMPLE

First few rows of the triangle are:

1;

3, 1;

4, 4, 1;

7, 8, 5, 1;

11, 15, 13, 6, 1;

18, 26, 28, 19, 7, 1;

...

(6,3) = 28 = 13 + 15 = (5,3) + (5,2).

MAPLE

L[1]:=1: L[2]:=3: for n from 3 to 12 do L[n]:=L[n-1]+L[n-2] od: T:=proc(n, k) if k=1 then L[n] elif n=1 then 0 else T(n-1, k)+T(n-1, k-1) fi end: for n from 1 to 12 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form - Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 01 2007

A000204 := proc(n) if n =1 then RETURN(1) ; elif n = 2 then RETURN(3) ; else RETURN( A000204(n-1)+A000204(n-2)) ; fi ; end ; A125608 := proc(nmax) local a, row, col, anext ; a := [1] ; row := 1 ; while nops(a) < nmax do row := row+1 ; a := [op(a), A000204(row)] ; for col from 2 to row-1 do anext := op(-row, a)+op(-row+1, a) ; a := [op(a), anext] ; od ; a := [op(a), 1] ; od ; RETURN(a) ; end ; A125608(80) ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 07 2007

CROSSREFS

Cf. A027973.

Sequence in context: A054907 A089554 A129246 * A099813 A141300 A014388

Adjacent sequences:  A125605 A125606 A125607 * A125609 A125610 A125611

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Nov 27 2006

EXTENSIONS

More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 01 2007

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 07 2007

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.