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A028412 Rectangular array of numbers Fibonacci(m(n+1))/Fibonacci(m), m>=1, n>=0, read by antidiagonals. 20
1, 1, 1, 1, 3, 2, 1, 4, 8, 3, 1, 7, 17, 21, 5, 1, 11, 48, 72, 55, 8, 1, 18, 122, 329, 305, 144, 13, 1, 29, 323, 1353, 2255, 1292, 377, 21, 1, 47, 842, 5796, 15005, 15456, 5473, 987, 34, 1, 76, 2208, 24447, 104005, 166408, 105937, 23184, 2584, 55, 1, 123, 5777 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Every integer-valued quotient of two Fibonacci numbers is in this array. [Clark Kimberling_, Aug 28 2008]

Not only does 5 divide row 5, but 50 divides (-1 + row 5), as in A214984. [Clark Kimberling_, Nov 02 2012]

REFERENCES

A. T. Benjamin and J. J. Quinn, Proofs that really count: the art of combinatorial proof, M.A.A. 2003, id. 142.

I. Strazdins, Lucas factors and a Fibonomial generating function, in Applications of Fibonacci numbers, Vol. 7 (Graz, 1996), 401-404, Kluwer Acad. Publ., Dordrecht, 1998.

LINKS

Clark Kimberling, Table of n, a(n) for n = 0..1829

FORMULA

T(n, m) = Sum[i_1>=0, Sum[i_2>=0, ... Sum[i_m>=0, C(n-i_m, i_1)*C(n-i_1, i_2)*C(n-i_2, i_3)*...*C(n-i_{m-1}, i_m) ] ... ]].

G.f. for column m>=1: 1/(1 - Lucas(m)*x + (-1)^m*x^2), where Lucas(m) = A000204(m). [Paul D. Hanna, Jan 28 2012]

EXAMPLE

1....1.....1.....1.......1........1....

1....3.....4.....7.......11.......18...

2....8.....17....48......122......323...

3....21....72....329.....1353.....5796,...

5....55....305...2255....15005....104005...

8....144...1292..15456...166408...1866294...

13...377...5473..105937..1845493..33489287,...

...

MATHEMATICA

max = 11; col[m_] := CoefficientList[ Series[ 1/(1 - LucasL[m]*x + (-1)^m*x^2), {x, 0, max}], x]; t = Transpose[ Table[ col[m], {m, 1, max}]] ; Flatten[ Table[ t[[n - m + 1, m]], {n, 1, max }, {m, n, 1, -1}]] (* From Jean-François Alcover, Feb 21 2012, after Paul D. Hanna *)

f[n_] := Fibonacci[n]; t[m_, n_] := f[m*n]/f[n]

TableForm[Table[t[m, n], {m, 1, 10}, {n, 1, 10}]] (* array *)

t = Flatten[Table[t[k, n + 1 - k], {n, 1, 120}, {k, 1, n}]] (* sequence *) (* Clark Kimberling, Nov 02 2012 *)

PROG

(PARI) {T(n, m)=polcoeff(1/(1 - Lucas(m)*x + (-1)^m*x^2 +x*O(x^n)), n)}

CROSSREFS

Columns include A000045, A001906, A001076, A004187, A049666, A049660, A049667, A049668, A049669, A049670. Rows include (essentially) A000032, A047946, A083564, A103226. Main diagonal is A051294.  Transpose is A214978.

Sequence in context: A092486 A159966 A119263 * A156699 A182236 A077819

Adjacent sequences:  A028409 A028410 A028411 * A028413 A028414 A028415

KEYWORD

tabl,nonn,easy,nice

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Erich Friedman, Jun 03 2001

Edited by Ralf Stephan, Feb 03 2005

Better description from Clark Kimberling, Aug 28 2008

STATUS

approved

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Last modified June 19 17:57 EDT 2013. Contains 226415 sequences.