A358435 Row sums of the triangular array A357498.

1, 4, 8, 16, 22, 36, 47, 68, 81, 105, 125, 155, 169, 220, 239, 300, 326, 365, 414, 475, 500, 572, 635, 705, 734, 830, 897, 966, 1009, 1151, 1195, 1318, 1373, 1490, 1566, 1672, 1734, 1903, 1971, 2107, 2221, 2390, 2461, 2580, 2689, 2887, 2963, 3176, 3276, 3450, 3580, 3789, 3868

Offset: 1

Author

Tamas Sandor Nagy, Nov 16 2022

Keywords

• nonn

Comments

The rows of the triangular array A357498 are chains of numbers that end with the positive terms of A007952.

Examples

			For row n=6, the next greater multiples are 6, 10, 12, 15, 16, and 17. These, divided by n..1 result in 1, 2, 3, 5, 8, and 17, the sum of which is a(6) = 36.
		

Crossrefs

Cf. A357498, A007952.

Programs

Mathematica

a[n_] := Module[{k = n, s = Table[0, n], r}, s[[1]] = 1; Do[k++; k += If[(r = Mod[k, i]) == 0, 0, i - Mod[k, i]]; s[[n + 1 - i]] = k/i, {i, n - 1, 1, -1}]; Total[s]]; Array[a, 50] (* Amiram Eldar, Nov 16 2022 *)

PARI

a(n) = my(v=vector(n)); v[1] = n; for (k=2, n, v[k] = v[k-1] + (n-k+1) - (v[k-1] % (n-k+1));); vecsum(vector(n, k, v[k]/(n-k+1))); \\ Michel Marcus, Nov 16 2022

Extensions

More terms from Thomas Scheuerle, Nov 16 2022