A067819 -id:A067819 - cp's OEIS frontend

A102716 Triangle read by rows: T(n,k) = sigma(binomial(n,k)) (0 <= k <= n), where sigma(m) is the sum of the positive divisors of m.

1, 1, 1, 1, 3, 1, 1, 4, 4, 1, 1, 7, 12, 7, 1, 1, 6, 18, 18, 6, 1, 1, 12, 24, 42, 24, 12, 1, 1, 8, 32, 48, 48, 32, 8, 1, 1, 15, 56, 120, 144, 120, 56, 15, 1, 1, 13, 91, 224, 312, 312, 224, 91, 13, 1, 1, 18, 78, 360, 576, 728, 576, 360, 78, 18, 1, 1, 12, 72, 288, 864, 1152, 1152, 864

Offset: 0

Emeric Deutsch, Feb 06 2005

Row n contains n+1 terms. Row sums yield A074801. T(2n,n) = A067819(n).

			T(6,3)=42 because the sum of the divisors of binomial(6,3)=20 is 1+2+4+5+10+20=42.
Triangle begins:
  1;
  1,  1;
  1,  3,  1;
  1,  4,  4,  1;
  1,  7, 12,  7,  1;

T. D. Noe, Rows n = 0..100 of triangle, flattened

Cf. A074801, A067819.

with(numtheory): T:=(n,k)->sigma(binomial(n,k)): for n from 0 to 11 do seq(T(n,k),k=0..n) od; # yields sequence in triangular form

Table[DivisorSigma[1,Binomial[n,k]],{n,0,20},{k,0,n}]//Flatten (* Harvey P. Dale, Mar 25 2016 *)

T(n, k) = sigma(binomial(n, k)) (0 <= k <= n).

cp's OEIS Frontend

A066972 Duplicate of A067819.

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A102716 Triangle read by rows: T(n,k) = sigma(binomial(n,k)) (0 <= k <= n), where sigma(m) is the sum of the positive divisors of m.

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