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A141674
Triangle T(n,m) read by rows: T(n,m) = sigma_0(n) * A126988(n,m).
1
1, 4, 2, 6, 0, 2, 12, 6, 0, 3, 10, 0, 0, 0, 2, 24, 12, 8, 0, 0, 4, 14, 0, 0, 0, 0, 0, 2, 32, 16, 0, 8, 0, 0, 0, 4, 27, 0, 9, 0, 0, 0, 0, 0, 3, 40, 20, 0, 0, 8, 0, 0, 0, 0, 4, 22, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 72, 36, 24, 18, 0, 12, 0, 0, 0, 0, 0, 6, 26, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 56, 28, 0, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 4
OFFSET
1,2
COMMENTS
Row sums are {1, 6, 8, 21, 12, 48, 16, 60, 39, 72}.
FORMULA
T(n,m) = sigma_0(n) * A126988(n,m).
T(n,m) = sigma_0(n) * if(m = 1, n, if(n mod m = 0, n/m, 0)).
EXAMPLE
Triangle begins
{ 1},
{ 4, 2},
{ 6, 0, 2},
{12, 6, 0, 3},
{10, 0, 0, 0, 2},
{24, 12, 8, 0, 0, 4},
{14, 0, 0, 0, 0, 0, 2},
{32, 16, 0, 8, 0, 0, 0, 4},
{27, 0, 9, 0, 0, 0, 0, 0, 3},
{40, 20, 0, 0, 8, 0, 0, 0, 0, 4}
MATHEMATICA
t[n_, m_] = DivisorSigma[0, n]*If[m == 1, n, If[Mod[n, m] == 0, n/m, 0]]; Table[Table[t[n, m], {m, 1, n}], {n, 1, 10}]; Flatten[%]
CROSSREFS
Cf. A126988.
Sequence in context: A180109 A019170 A107504 * A329323 A178394 A266391
KEYWORD
nonn,tabl,easy,less
AUTHOR
EXTENSIONS
Edited by the Associate Editors of the OEIS, Jun 10 2018
STATUS
approved