A108036 - OEIS

A108036

Triangle read by rows: the triangle in A108035 surrounded by a border of 0's.

0, 0, 0, 0, 1, 0, 0, 2, 2, 0, 0, 3, 3, 3, 0, 0, 5, 5, 5, 5, 0, 0, 8, 8, 8, 8, 8, 0, 0, 13, 13, 13, 13, 13, 13, 0, 0, 21, 21, 21, 21, 21, 21, 21, 0, 0, 34, 34, 34, 34, 34, 34, 34, 34, 0, 0, 55, 55, 55, 55, 55, 55, 55, 55, 55, 0, 0, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 0, 0, 144, 144, 144, 144

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

0,8

LINKS

Table of n, a(n) for n=0..82.

FORMULA

G.f.: x*y*(1+x+y)/((1-x-x^2)*(1-y-y^2)). [U coordinates]

EXAMPLE

0; 0,0; 0,1,0; 0,2,2,0; 0,3,3,3,0; 0,5,5,5,5,0; ...

PROG

(Python)

from math import isqrt