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A156346
Palindromic period of length 12: repeat 1,2,-4,4,-2,-1,-1,-2,4,-4,2,1.
2
1, 2, -4, 4, -2, -1, -1, -2, 4, -4, 2, 1, 1, 2, -4, 4, -2, -1, -1, -2, 4, -4, 2, 1, 1, 2, -4, 4, -2, -1, -1, -2, 4, -4, 2, 1, 1, 2, -4, 4, -2, -1, -1, -2, 4, -4, 2, 1
OFFSET
0,2
FORMULA
a(n) == A154811(n) (mod 9).
a(n) = ( (2*A154811(n)) mod 9 ) - A154811(n).
G.f.: -(x-1)*(x^4+3*x^3-x^2+3*x+1) / ( (1+x^2)*(x^4-x^2+1) ). - R. J. Mathar, Mar 08 2011
MATHEMATICA
PadRight[{}, 50, {1, 2, -4, 4, -2, -1, -1, -2, 4, -4, 2, 1}] (* Harvey P. Dale, May 29 2021 *)
CROSSREFS
Cf. A156283.
Sequence in context: A107500 A108620 A070512 * A156283 A126123 A285349
KEYWORD
easy,sign
AUTHOR
Paul Curtz, Feb 08 2009
STATUS
approved