OFFSET
0,3
FORMULA
G.f. of column k (for k > 1): (1/(1 - x)) * Sum_{j>=0} x^(k^j)/(1 - x^(k^j)).
EXAMPLE
Square array begins:
0, 0, 0, 0, 0, 0, ...
2, 1, 1, 1, 1, 1, ...
6, 3, 2, 2, 2, 2, ...
12, 4, 4, 3, 3, 3, ...
20, 7, 5, 5, 4, 4, ...
30, 8, 6, 6, 6, 5, ...
MATHEMATICA
Table[Function[k, Sum[Floor[n/k^j], {j, 0, n}]][i - n + 1], {i, 0, 12}, {n, 0, i}] // Flatten
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Ilya Gutkovskiy, Feb 22 2019
STATUS
approved