OFFSET
0,2
COMMENTS
Ternary representation of terms in n-th row have n rightmost adjacent zeros.
Row sums = A141397: (1, 5, 19 62, 193, 587, ...).
LINKS
Ivan Neretin, Table of n, a(n) for n = 0..5049
FORMULA
Triangle read by rows, descending antidiagonals of the multiplication table: (top row, numbers not multiples of 3); leftmost column, 3^n.
EXAMPLE
The array begins:
1, 2, 4, 5, 7, ...
3, 6, 12, 15, 21, ...
9, 18, 36, 45, 63, ...
27, 54, 108, 135, 189, ...
81, 162, 324, 405, 567, ...
...
Descending antidiagonals of the array give
1;
2, 3;
4, 6, 9;
5, 12, 18, 27;
7, 15, 36, 54, 81;
8, 21, 45, 108, 162, 243;
10, 24, 63, 135, 324, 486, 729;
11, 30, 72, 189, 405, 972, 1458, 2187;
...
MATHEMATICA
Flatten[Table[3^k*Quotient[(3 (m - k) - 1), 2], {m, 0, 10}, {k, 0, m - 1}]] (* Ivan Neretin, Nov 26 2016 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jun 29 2008
STATUS
approved