OFFSET
0,2
COMMENTS
Row sums = A000566, the heptagonal numbers: (1, 7, 18, 34, 55, ...).
FORMULA
By rows, (n+1) terms of 3n+1, 3n, 3n-1, ...
EXAMPLE
First few rows of the triangle:
1;
4, 3;
7, 6, 5;
10, 9, 8, 7;
13, 12, 11, 10, 9;
16, 15, 14, 13, 12, 11;
19, 18, 17, 16, 15, 14, 13;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 08 2007
EXTENSIONS
a(5) = 5, a(30) = 20 corrected and more terms from Georg Fischer, Jun 07 2023
STATUS
approved