A099558 Antidiagonal sums of the triangle A099557.

1, 1, 2, 3, 4, 6, 9, 14, 22, 34, 52, 79, 120, 183, 280, 429, 657, 1005, 1536, 2347, 3587, 5484, 8386, 12824, 19609, 29981, 45837, 70079, 107145, 163820, 250476, 382969, 585541, 895258, 1368795, 2092808, 3199790, 4892313, 7480094, 11436670

Offset

0,3

Links

Michael De Vlieger, Table of n, a(n) for n = 0..5423

Hùng Việt Chu and Zachary Louis Vasseur, Linear Recurrences of Generalized Schreier Sets Revisited, J. Int. Seq. 29 (2026), Article 26.2.2. See p. 3 (Table 1).

Formula

G.f.: (1-x+x^2)/((1-x)^2-x^5).

Mathematica

CoefficientList[Series[(1 - x + x^2)/((1 - x)^2 - x^5), {x, 0, 39}], x] (* Michael De Vlieger, Apr 08 2026 *)

Prog

(PARI) a(n)=polcoeff((1-x+x^2)/((1-x)^2-x^5)+x*O(x^n), n)

Crossrefs

Cf. A099557.

Sequence in context: A214041 A058355 A179041 * A018140 A256969 A005579

Adjacent sequences: A099555 A099556 A099557 * A099559 A099560 A099561

Keyword

nonn

Author

Paul D. Hanna, Oct 22 2004

Status

approved