A165747 a(n) = 1-2n.

1, -1, -3, -5, -7, -9, -11, -13, -15, -17, -19, -21, -23, -25, -27, -29, -31, -33, -35, -37, -39, -41, -43, -45, -47, -49, -51, -53, -55, -57, -59, -61, -63, -65, -67, -69, -71, -73, -75, -77, -79, -81, -83, -85, -87, -89, -91, -93, -95, -97, -99, -101, -103

Offset: 0

Author

Philippe Deléham, Sep 26 2009

Keywords

• easy
• sign

Links

• G. C. Greubel, Table of n, a(n) for n = 0..1000
• Ângela Mestre, José Agapito, Square Matrices Generated by Sequences of Riordan Arrays, J. Int. Seq., Vol. 22 (2019), Article 19.8.4.
• Index entries for linear recurrences with constant coefficients, signature (2, -1).

Crossrefs

Cf. A060747

Programs

Mathematica

Table[1 - 2 n, {n, 0, 100}] (* G. C. Greubel, Apr 07 2016 *)

PARI

x='x+O('x^99); Vec((1-3*x)/(1-x)^2) \\ Altug Alkan, Apr 07 2016

Formula

a(n) = -A060747(n).

a(n) = 2*a(n-1) - a(n-2), a(0)= 1, a(1)= -1.

G.f.: (1-3x)/(1-x)^2.

a(n) = Sum_{k, 0<=k<=n} A112555(n,k)*(-2)^(n-k).

E.g.f.: (1-2*x)*exp(x). - G. C. Greubel, Apr 07 2016