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A108931 a(2n) = -A106328(n), a(2n+1) = A054488(n). 0
0, 1, -3, 8, -18, 47, -105, 274, -612, 1597, -3567, 9308, -20790, 54251, -121173, 316198, -706248, 1842937, -4116315, 10741424, -23991642, 62605607, -139833537, 364892218, -815009580, 2126747701, -4750223943, 12395593988, -27686334078, 72246816227 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..29.

FORMULA

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

MAPLE

seriestolist(series(x*(2*x-1)*(x-1)/((x^2+2*x-1)*(x^2-2*x-1)), x=0, 30)); -or- Floretion Algebra Multiplication Program, FAMP Code: 1jescycrokseq[ + 'jj' + 'kk' + 'ij'] Roktype is set to: Y[sqa.Findk()] = Y[sqa.Findk()] + 1/2;

CROSSREFS

Cf. A106328, A054488.

Sequence in context: A026384 A066143 A110045 * A032100 A226593 A023371

Adjacent sequences:  A108928 A108929 A108930 * A108932 A108933 A108934

KEYWORD

easy,sign

AUTHOR

Creighton Dement, Jul 20 2005

STATUS

approved

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Last modified August 21 21:36 EDT 2017. Contains 290908 sequences.