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A131321 Triangle read by rows: A168561^2. 2
1, 0, 1, 2, 0, 1, 0, 4, 0, 1, 5, 0, 6, 0, 1, 0, 14, 0, 8, 0, 1, 13, 0, 27, 0, 10, 0, 1, 0, 46, 0, 44, 0, 12, 0, 1, 34, 0, 107, 0, 65, 0, 14, 0, 1, 0, 145, 0, 204, 0, 90, 0, 16, 0, 1, 89, 0, 393, 0, 345, 0, 119, 0, 18, 0, 1, 0, 444, 0, 854, 0, 538, 0, 152, 0, 20, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Left border, nonzero terms = odd indexed Fibonacci numbers: (1, 2, 5, 13, ...). Next column, nonzero terms = A030267: (1, 4, 14, 46, 145, ...). Row sums = A131322: (1, 1, 3, 5, 12, 23, 51, ...).

Riordan array (f(x),x*f(x)) where f(x) = (1-x^2)/(1-3*x^2+x^4). Aerated version of triangle in A188137. - Philippe Deléham, Jan 26 2012

LINKS

Table of n, a(n) for n=0..77.

FORMULA

A168561 squared, as an infinite lower triangular matrix.

EXAMPLE

First few rows of the triangle are:

   1;

   0,  1;

   2,  0,  1;

   0,  4,  0,  1;

   5,  0,  6,  0,  1;

   0, 14,  0,  8,  0,  1;

  13,  0, 27,  0, 10,  0,  1;

  ...

MAPLE

F:= (n, k)-> coeff(combinat[fibonacci](n+1, x), x, k):

T:= (n, k)-> add(F(n, j)*F(j, k), j=0..n):

seq(seq(T(n, k), k=0..n), n=0..14);  # Alois P. Heinz, Dec 12 2019

CROSSREFS

Cf. A049310, A030267, A168561, A188137.

Sequence in context: A053389 A202328 A136688 * A111959 A110109 A145973

Adjacent sequences:  A131318 A131319 A131320 * A131322 A131323 A131324

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson, Jun 28 2007

STATUS

approved

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Last modified May 28 21:37 EDT 2020. Contains 334690 sequences. (Running on oeis4.)