A382311 Antidiagonal sums of A382310.

0, 5, 15, 28, 52, 81, 123, 176, 240, 325, 425, 542, 684, 849, 1037, 1250, 1498, 1775, 2083, 2424, 2806, 3227, 3687, 4188, 4732, 5329, 5973, 6666, 7410, 8207, 9065, 9982, 10958, 11995, 13095, 14260, 15500, 16809, 18189, 19642, 21170, 22775, 24465, 26238, 28094, 30035

Offset: 0

Author

Stefano Spezia, Mar 21 2025

Keywords

• nonn

Crossrefs

Cf. A382310.

Programs

Mathematica

a[n_]:=(2(6n^2-30n-23)Floor[n-2Sqrt[n+1]]-(12n-6)Floor[n-2Sqrt[n+1]]^2+4Floor[n-2Sqrt[n+1]]^3-84-61n+45n^2-2n^3)/6; Array[a,46,0]

Formula

a(n) = (2*(6*n^2 - 30*n - 23)*floor(n-2*sqrt(n+1)) - (12*n - 6)*floor(n - 2*sqrt(n+1))^2 + 4*floor(n - 2*sqrt(n+1))^3 - 84 - 61*n + 45*n^2 - 2*n^3)/6.

a(n) ~ n^3/3.