OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..10000
FORMULA
T(n,k) = 0 if 2k > n+1. T(n,k) = k if 2k=n+1. T(n,k)=2k if 2k=n. T(n,k) = 3k if 2k <= n-1.
EXAMPLE
First few rows of the triangle are:
1;
2, 0;
3, 2, 0;
3, 4, 0, 0;
3, 6, 3, 0, 0;
3, 6, 6, 0, 0, 0;
3, 6, 9, 4, 0, 0, 0;
3, 6, 9, 8, 0, 0, 0, 0;
3, 6, 9, 12, 5, 0, 0, 0, 0;
3, 6, 9, 12, 10, 0, 0, 0, 0, 0;
3, 6, 9, 12, 15, 6, 0, 0, 0, 0, 0;
3, 6, 9, 12, 15, 12, 0, 0, 0, 0, 0, 0;
...
MATHEMATICA
fs[n_, k_]:=Which[2k>n+1, 0, 2k==n+1, k, 2k==n, 2k, 2k<=n-1, 3k]; Flatten[ Table[ fs[n, k], {n, 15}, {k, n}]] (* Harvey P. Dale, Mar 06 2013 *)
CROSSREFS
KEYWORD
AUTHOR
Gary W. Adamson, Jun 25 2012
STATUS
approved