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A248158 Expansion of (1 - 2*x^2)/(1 + x)^3. Second column of Riordan triangle A248156. 3
1, -3, 4, -4, 3, -1, -2, 6, -11, 17, -24, 32, -41, 51, -62, 74, -87, 101, -116, 132, -149, 167, -186, 206, -227, 249, -272, 296, -321, 347, -374, 402, -431, 461, -492, 524, -557, 591, -626, 662, -699, 737, -776, 816, -857, 899, -942, 986 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

This is the column k=1 sequence of the Riordan triangle A248156 without a leading zero.

LINKS

Table of n, a(n) for n=0..47.

Index entries for linear recurrences with constant coefficients, signature (-3,-3,-1).

FORMULA

O.g.f.: (1 - 2*x^2)/(1 + x)^3 = -2/(1 + x) + 4/(1 + x)^2 - 1/(1 + x)^3.

a(n) = (-1)^n*(4*(2*n+1) - (n+1)*(n+2))/2, n >= 0.

a(n) = -3*(a(n-1) + a(n-2)) - a(n-3), n >= 3 with a(0) = 1, a(1) = -3 and a(2) = 4.

a(n) = (-1)^(n+1)*A046691(n-5). - R. J. Mathar, Mar 13 2021

a(n)+a(n+1) = A248157(n+1). - R. J. Mathar, Mar 13 2021

CROSSREFS

Cf. A046691, A148157, A248156(n+1,1).

Sequence in context: A249618 A073498 A105736 * A090283 A318705 A334492

Adjacent sequences:  A248155 A248156 A248157 * A248159 A248160 A248161

KEYWORD

sign,easy

AUTHOR

Wolfdieter Lang, Oct 05 2014

STATUS

approved

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Last modified September 25 17:35 EDT 2022. Contains 356986 sequences. (Running on oeis4.)