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A127651
Triangle T(n,k) = n*k if k|n, 0 otherwise; 1<=k<=n.
1
1, 2, 4, 3, 0, 9, 4, 8, 0, 16, 5, 0, 0, 0, 25, 6, 12, 18, 0, 0, 36, 7, 0, 0, 0, 0, 0, 49, 8, 16, 0, 32, 0, 0, 0, 64, 9, 0, 27, 0, 0, 0, 0, 0, 81, 10, 20, 0, 0, 50, 0, 0, 0, 0, 100, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 121, 12, 24, 36, 48, 0, 72, 0, 0, 0, 0, 0, 144
OFFSET
1,2
COMMENTS
Equals the matrix product A127648 * A127093 as infinite lower triangular matrices.
FORMULA
T(n,k) = n*A127093(n,k). - R. J. Mathar, Oct 01 2011
EXAMPLE
First few rows of the triangle are:
1;
2, 4;
3, 0, 9;
4, 8, 0, 16;
5, 0, 0, 0, 25;
6, 12, 18, 0, 0, 36;
7, 0, 0, 0, 0, 0, 49;
8, 16, 0, 32, 0, 0, 0, 64;
...
MAPLE
A127651 := proc(n, k)
if n mod k =0 then
n*k;
else
0 ;
end if;
end proc: # R. J. Mathar, Oct 01 2011
CROSSREFS
Cf. A127648, A127093, A064987 (row sums).
Sequence in context: A246713 A106137 A213381 * A019641 A085008 A285587
KEYWORD
nonn,tabl,easy
AUTHOR
Gary W. Adamson, Jan 22 2007
STATUS
approved