A353154 Sum of the even-indexed terms in the n-th row of the triangle A196020.

0, 0, 1, 0, 3, 0, 5, 0, 7, 1, 9, 0, 11, 3, 13, 0, 15, 5, 17, 0, 20, 7, 21, 0, 23, 9, 28, 0, 27, 11, 29, 0, 36, 13, 33, 1, 35, 15, 44, 0, 39, 17, 41, 3, 52, 19, 45, 0, 47, 21, 60, 5, 51, 23, 54, 0, 68, 25, 57, 7, 59, 27, 76, 0, 66, 29, 65, 9, 84, 31, 69, 0, 71, 33, 97, 11, 75, 36, 77, 0

Offset: 1

Author

Omar E. Pol, Apr 27 2022

Keywords

• nonn

Comments

Conjecture: indices of zeros give A082662.

a(n) is the total number of steps in all even-indexed double-staircases of the diagram of A196020 with n levels.

a(n) is also the total number of steps in all even-indexed double-staircases of the diagram described in A335616 with n levels that have at least one step in the bottom level of the diagram.

The graph of the sum-of-divisors function A000203 is intermediate between the graph of A353149 and the graph of this sequence (see the Links section). - Omar E. Pol, May 13 2022

Examples

			For n = 15 the 15th row of the triangle A196020 is [29, 13, 7, 0, 1]. The sum of the even-indexed terms is 13 + 0 = 13, so a(15) = 13.
		

Links

• OEIS Plot 2, A353154 vs A000203

Crossrefs

Cf. A000203, A057641, A082662, A196020, A209246, A211343, A235791, A236104, A237591, A237593, A285901, A335616, A347186, A353149.

Formula

a(n) = A353149(n) - A000203(n).

a(n) = A209246(n) - A353149(n).