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A048570
Triangle T(n,k) = number of divisors of binomial(n,k).
4
1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 3, 4, 3, 1, 1, 2, 4, 4, 2, 1, 1, 4, 4, 6, 4, 4, 1, 1, 2, 4, 4, 4, 4, 2, 1, 1, 4, 6, 8, 8, 8, 6, 4, 1, 1, 3, 9, 12, 12, 12, 12, 9, 3, 1, 1, 4, 6, 16, 16, 18, 16, 16, 6, 4, 1, 1, 2, 4, 8, 16, 16, 16, 16, 8, 4, 2, 1, 1, 6, 8, 12, 12, 24, 24, 24
OFFSET
0,5
FORMULA
T(n, k) = A000005(A007318(n, k)). - Michel Marcus, Mar 07 2020
EXAMPLE
Triangle begins
1;
1, 1;
1, 2, 1;
1, 2, 2, 1;
1, 3, 4, 3, 1;
1, 2, 4, 4, 2, 1;
1, 4, 4, 6, 4, 4, 1;
...
MATHEMATICA
Flatten[Table[DivisorSigma[0, Binomial[n, k]], {n, 0, 12}, {k, 0, n}]] (* Stefano Spezia, Apr 07 2022 *)
PROG
(PARI) T(n, k) = if (n>=k, numdiv(binomial(n, k))); \\ Michel Marcus, Mar 07 2020
CROSSREFS
Sequence in context: A156044 A180980 A275298 * A090806 A241926 A174446
KEYWORD
nonn,tabl,easy
STATUS
approved