A144824 Triangle read by rows, A054533 * A127648 (matrix product).
1, -1, 2, -1, -2, 6, 0, -4, 0, 8, -1, -2, -3, -4, 20, 1, -2, -6, -4, 5, 12, -1, -2, -3, -4, -5, -6, 42, 0, 0, 0, -16, 0, 0, 0, 32, 0, 0, -9, 0, 0, -18, 0, 0, 54, 1, -2, 3, -4, -20, -6, 7, -8, 9, 40, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, 110
Offset: 1
Examples
Triangle A054533 starts as follows: 1; -1, 1; -1, -1, 2; 0, -2, 0, 2; -1, -1, -1, -1, 4; 1, -1, -2, -1, 1, 2; ... The first few rows of triangle A144824 are as follows: 1; -1, 2; -1, -2, 6; 0, -4, 0, 8; -1, -2, -3, -4, 20; 1, -2, -6, -4, 5, 12; -1, -2, -3, -4, -5, -6, 42; ...
Links
- Jinyuan Wang, Table of n, a(n) for n = 1..10000
Formula
Triangle read by rows, A054533 * A127648 (matrix product). The operation is equivalent to taking termwise products of row A054533 terms and the natural numbers.
T(n, k) = k * Sum_{d|gcd(n,k)} d * mu(n/d) for n >= 1 and 1 <= k <= n. - Petros Hadjicostas, Jul 28 2019
Comments