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A172342 Triangle t(n,k) read by rows: fibonomial ratios c(n)/(c(k)*c(n-k)) where c are partial products of a generalized Fibonacci sequence with multiplier m=5. 2
1, 1, 1, 1, 5, 1, 1, 26, 26, 1, 1, 135, 702, 135, 1, 1, 701, 18927, 18927, 701, 1, 1, 3640, 510328, 2649780, 510328, 3640, 1, 1, 18901, 13759928, 370988828, 370988828, 13759928, 18901, 1, 1, 98145, 371007729, 51941082060, 269708877956 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Start from the generalized Fibonacci sequence A052918 and its partial products c(n) = 1, 1, 5, 130, 17550, 12302550, 44781282000,... Then t(n,k) = c(n)/(c(k)*c(n-k)).

Row sums are 1, 2, 7, 54, 974, 39258, 3677718, 769535316, 374333253826, 406720191959532,...

LINKS

Table of n, a(n) for n=0..40.

EXAMPLE

1;

1, 1;

1, 5, 1;

1, 26, 26, 1;

1, 135, 702, 135, 1;

1, 701, 18927, 18927, 701, 1;

1, 3640, 510328, 2649780, 510328, 3640, 1;

1, 18901, 13759928, 370988828, 370988828, 13759928, 18901, 1;

1, 98145, 371007729, 51941082060, 269708877956, 51941082060, 371007729, 98145, 1;

MATHEMATICA

Clear[f, c, a, t];

f[0, a_] := 0; f[1, a_] := 1;

f[n_, a_] := f[n, a] = a*f[n - 1, a] + f[n - 2, a];

c[n_, a_] := If[n == 0, 1, Product[f[i, a], {i, 1, n}]];

t[n_, m_, a_] := c[n, a]/(c[m, a]*c[n - m, a]);

Table[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}], {a, 1, 10}];

Table[Flatten[Table[Table[t[n, m, a], {m, 0, n}], {n, 0, 10}]], {a, 1, 10}]

CROSSREFS

Cf. A010048 (m=1), A099927 (m=2), A172339 (m=3), A172343 (m=6).

Sequence in context: A203346 A176793 A118190 * A143213 A172377 A156587

Adjacent sequences:  A172339 A172340 A172341 * A172343 A172344 A172345

KEYWORD

nonn,tabl,easy

AUTHOR

Roger L. Bagula, Feb 01 2010

STATUS

approved

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Last modified February 21 04:55 EST 2020. Contains 332086 sequences. (Running on oeis4.)