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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
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 * A360268 A090283 A318705
KEYWORD
sign,easy
AUTHOR
Wolfdieter Lang, Oct 05 2014
STATUS
approved

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Last modified March 29 08:47 EDT 2024. Contains 371267 sequences. (Running on oeis4.)