A131245 A046854^2 as an infinite lower triangular matrix.

1, 2, 1, 3, 2, 1, 5, 5, 2, 1, 8, 9, 7, 2, 1, 13, 19, 13, 9, 2, 1, 21, 33, 34, 17, 11, 2, 1, 34, 65, 61, 53, 21, 13, 2, 1, 55, 111, 141, 97, 76, 25, 15, 2, 1, 89, 210, 248, 257, 141, 103, 29, 17, 2, 1, 144, 355, 534, 461, 421, 193, 134, 33, 19, 2, 1

Offset: 0

Author

Gary W. Adamson, Jun 22 2007

Keywords

• nonn
• tabl

Comments

Left border = Fibonacci numbers.

Row sums = A131246.

A131243 is the square of the reflection triangle to A046854: A065941.

Row sums of A131243 = (1, 3, 6, 14, 30, 67, 146, 322, 705, 1549, ...).

Examples

			First few rows of the triangle:
   1;
   2,  1;
   3,  2,  1;
   5,  5,  2,  1;
   8,  9,  7,  2,  1;
  13, 19, 13,  9,  2,  1;
  21, 33, 34, 17, 11,  2,  1;
  ...
		

Crossrefs

Cf. A131243, A131244, A131246, A046854, A065941.

Programs

PARI

T(n, k) = binomial((n+k)\2, k);
row(n) = my(m=matrix(n+1, n+1, i, j, T(i-1,j-1))); vector(n+1, i, (m^2)[n+1,i]);
lista(nn) = for (n=0, nn, my(v=row(n)); for (i=1, #v, print1(v[i], ", "));); \\ Michel Marcus, Feb 28 2022

Extensions

More terms from Michel Marcus, Feb 28 2022