OFFSET
1,14
EXAMPLE
--------------------------------------------------------
Illustration of first five
slices of the tetrahedron Row sum
--------------------------------------------------------
. 1, 1
. 1, 1
. 1, 1, 2
. 1, 1
. 1, 1, 2
. 1, 1, 1, 3
. 1, 1
. 1, 1, 2
. 2, 1, 1, 4
. 1, 2, 1, 1, 5
. 1, 1
. 1, 1, 2
. 2, 1, 1, 4
. 2, 2, 1, 1, 6
. 1, 2, 2, 1, 1, 7
--------------------------------------------------------
. 1, 2, 1, 3, 2, 1, 5, 4, 2, 1, 7, 6, 4, 2, 1,
.
It appears that column sums give A058399.
Also, written as a triangle read by rows in which each row is a flattened triangle, begins:
1;
1,1,1,
1,1,1,1,1,1;
1,1,1,2,1,1,1,2,1,1;
1,1,1,2,1,1,2,2,1,1,1,2,2,1,1;
1,1,1,2,1,1,3,2,1,1,3,3,2,1,1,1,3,3,2,1,1;
1,1,1,2,1,1,3,2,1,1,4,3,2,1,1,3,4,3,2,1,1,1,3,4,3,2,1,1;
In which row sums give A006128.
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Apr 22 2012
STATUS
approved